I looked at the Arm’s Reach because of metafilter, but I’m going with a Pack and Play because they are cheaper and bigger in size. A friend of mine used a Pack and Play with both of hers, so I know they are fine. Our bed is a good size for one, although I was prepared to raise it a bit if necessary. The best part about the Pack and Play is that it’s very portable, and can be used as a playbin or a toy storage bin, so we expect to get a lot of use out of it.
I had an Arm’s Reach. My daughter didn’t like it. She slept in a bouncinette on the floor for quite some time, in our bed occasionally after she was about 3-4 months and then in a crib in her own room for about 6 months before she graduated to a full-sized mattress on the floor (she thrashed so much she would hit her head on the crib).
Tried to find one on amazon to demonstrate what they looked like, but couldn’t find one. I guess they don’t make them anymore. I think the next best thing could be a bouncy seat, though I’m not sure what the recommendation is about a baby sleeping in one overnight. I will tell you that babies are snotty, pretty much from birth to age 2, and it does interfere with their sleep. Well, mine were like that anyway. We got to the point where my daughter would grab the snot sucker from my hand and stick it up her own nose (yes I was there to make sure it didn’t go in too far).
I decided that the Arm’s Reach thing looked a little too flimsy. We used a regular crib instead. We took one of the sides off (the one that’s meant to be adjustable) and used bungee cords to strap the crib tightly to the bed. There was still a little gap, which I filled with foam batting and tightly covered with a sheet. This meant that the baby had his own place to sleep but was still basically in bed with us.
Now, as time went on and he got older and bigger and I felt safer about having him in the actual bed, we did that too, but we left the crib attached because it basically let me have a place to fling my arm into and made it feel like our bed was a little bigger.
I want to talk about nursing laying down, too … I think it’s absolutely fabulous and I wish I had latched on to it (ha!) when my first few kids were wee. Really — you can sleep and nurse and nothing could be easier.
Also, if you have a co-sleeper, you can nurse the baby lying down and there’s no “OMG is he going to wake when I transfer him to the crib?” problem. Just arise from the bed and go about your business and the babeling is down for the night. Well, down for at least however long he’ll sleep this time. 
I LOVED nursing laying down. It made it so much easier to do. I wish I had mastered it with my first - I probably would’ve been able to nurse more than I did. I always thought of nursing laying down as the black belt nursing skill and being able to nurse in public without flashing everyone in a 10-foot radius the skills of a true master. I have no life.
Honey, I have nursed everywhere a baby can go, and no one’s seen my goods that I’m aware of. Even nursing a newborn, though, I’m not much more than a B cup, so I’m sure that helps.
Ellen, ninja nurser
I don’t know why I couldn’t manage it. Things just never seemed to line up properly. It could be related to having enormous boobs. Getting the nipple in his mouth was like pushing a rope. Also, it’s hard to figure things out when you are terribly sleep deprived. Nursing was really, really difficult for me. Those nursing hormones that everyone else seems to think feel delicious just made me feel like an exhausted, raging bitch–the way you feel when you are sharply awoken from a very sound sleep. So I was never in the mood to experiment. We are still nursing a little, but we have our routine down and it doesn’t seem worth bothering with at this point.
With my oldest, I couldn’t nurse him lying down until he was maybe around 4-5 months old or so. Maybe even a little older. With the other two, we figured it out almost instantly. I don’t know whether it was just me having experience or whether they were just naturally better at it or what. It did make nighttime feedings a lot more pleasant, though.
We had an Arm’s Reach mini co-sleeper and used it with both kids. It was nice having them right next to the bed so I could reach in and get them without having to get up. The mini co-sleeper is quite small, so you can only use it with a very young baby. This worked out well for us, since I couldn’t sleep well with a baby in the room. Once they were sleeping slightly longer stretches, we moved them to their own room. Then I’d either nurse them in their room or my husband would bring them to me to nurse in bed.
We had an Arms reach. Mozling hated it, as she hated her crib. Ended up co-sleeping in the bed out of desperation, which sort of worked (she never has been the best sleeper).
To those who think the Arms Reach is flimsy, it most certainly is not. It is very sturdy; frankly, it is heavy as f*ck.
We use it for storage now.
We also had the Arms Reach and our daughter slept on it for probably five whole minutes. Then we began using it as a changing station which also didn’t work for our backs because of the height. She just slept in between us on the bed and I was hesitant in the beginning, but getting 4-5 hours of uninterrupted sleep was just awesome!
She still sleeps with me on the bed but she gets her own set of baby blankets because she gets hot and sweaty otherwise. I need my thick comforters. She wakes up once at night and I sometimes nurse her laying down, but it is just easy for me to get up and use my nursing chair and brest friend. She doesn’t even open her eyes really. She nurses for 15-20 min and goes right back to sleep on the bed for another 4-5 hrs.
But yes, it is sturdy and it would’ve been great if Maya had actually slept on it.
That looks like the “small cradles” that I’ve seen around all my life, for when a bassinet (I think that’s the right term) is not useful any more but the baby is still small enough to need frequent feedings. The ones here are not for keeping beside the bed and have it act as a sort of extension, tho: the logistics of that simply wouldn’t work in most Spanish bedrooms (Mom would need to push the cradle out of the way to get up). When the baby needs food, the parent who’s less sluggish crawls out of bed, checks that it’s indeed hunger, puts baby to breast and lies back down; when baby is done eating, Mom puts it back in the cradle.
I have no idea what the nomenclature will be Over There, but Over Here in Spain cradles come in different widths and lengths; the one Sil and Bro used to have their second kid in their bedroom is the foldable travel cradle/playpen. The things you have to look for and be careful about are the same for any cradle size.
We had twins 11 years ago.
We used a club chair (similar to this) that we already had and wedged it between the bed and wall on my wifes side of the bed. It was too low for our bed and deep matress so I propped it up on blocks. The chair could not move. The edge of the seat was a couple of inches lower than the edge of the bed to ensure that the kids wouldn’t roll out. We put them in the chair with their heads facing the bed and feet to the back of the chair. Since there were 2 of them, they couldn’t roll around at all.
It was very useful to have them close so we could see what they were up to when they made their baby noises in the night.
We used it for a couple of months until they got too big and moved them into a crib in their own room. They shared the crib for another couple of months until they got too active when sleeping and started thumping their feet on the matress, then they got their own cribs.