The folks across the street finished moving out yesterday. That means new people will be moving in soon. (We aren’t sure when; we kinda forgot to ask our old neighbors that question.) What should my wife and I do to greet the new people? I think it would be cool to do something slightly “different,” but not so unusual that they’ll never speak to us again. We’re a pretty laid-back, quiet, young couple, so knocking on their front door and saying “Hi, wanna wife-swap?” is probably out. My wife makes awesome desserts so that’s always an option, but it’s fairly “standard” as far as new neighbor greetings go. Any other ideas?
What a nice thing to do! And dessert is a standard because it is usually pretty welcome! But you could also drop off a jar of spaghetti sauce, some boxed pasta and some parmesean cheese so they can make an easy first meal in their new house - and include a list with important or useful neighborhood information, such as the zip code, what day is trash day or recycle day, the location of a couple of nearby grocery stores, some dentist, doctor or vet references, info about the homeowners association, and what time the mail generally arrives each day.
“We welcome our new overlords” springs to mind. 
Seriously, the dessert is a very good thing. Sure, it’s tried and true, but it’s a good, friendly gesture. Sharing food is always a good thing for creating a bond, and dessert must surely qualify as the friendliest kind of food.
Show up with a bowl with yours and your spouse’s car keys in it, hold it out and wink lewdly.
When go, take pie!
Dress like 1960s-stereotype cannibals.
Tell them you’d love to have them for dinner.
That sould have been “1960s-sitcom stereotype cannibals”.
And some groups mayn’t take that too well.
Two other useful phone numbers/addresses: a good pizza place and a video store.
You can’t go wrong with the tried and true introductory butt sniffing. For best impressions remember to warm your nose immediately before visiting. Also, offer your own butt immediately after you sniff. It’s rude to make the new neighbors walk around you for their turn.
Yay, it’s so nice that people still do this. I’ve been in my apartment building for nearly 3 years and I don’t know a single other tenant. 
I like the dessert and local info/phone numbers idea. Maybe even take them one of your junk mail Val-u-Pak envelopes with the local coupons for everything from pizza to muffler repair. I’d also add the names and numbers of a few good babysitters, if you know them and the new family may have kids or grandkids. (It’s really hard to find new babysitters when you move!)
Finally, write down your name and your wife’s name, with your phone number if you want to give it to them. They won’t remember your name the next day, and they’ll feel really bad about it, because you were so nice to them.
When we were moving into our house, one of our new neighbors called me at work to ask if it was “okay” if she brought us dinner that night (well, yeah!), and if we liked roast beef sandwiches (of course!). That night after I got home, she brought over a layered carrying container and a bottle of barbecue sauce. Opening each layer was a fun surprise for us. At the top there was a plate full of really yummy and tender roast beef. Buns, fresh fruit and veggies, and Rice Krispie bars rounded out the menu. It was a simple dinner, but we had fun with it and appreciated it very much. We only wished she had agreed to stay and eat it with us!
Conversely, if you move into a new house and the 1960s-sitcom stereotype cannibals across the street come over and capture you, just remember all you have to say is Pulu se bagumba.*
You had to be there.
What is this dessert of which you speak? Where I’m from the prescribed welcome (or thank you, for that matter) food is banana nut bread. And you have to wrap it in colored saran wrap.
Zucchini bread is only okay if you already know you don’t like them.
Two words: Garden Gnome.
I think you ought to greet them in the manner demonstrated in the highly educational game The Sims: Ring their doorbell and give them each a cursory greeting, then go inside, help yourself to their food, watch their television, and play with their toys. Use their toilet often. Make friends with them by juggling and reciting limericks, and if you’re feeling playful, tickling them. If they don’t have interesting things, wander off in a bored huff.
I take 'em a loaf of homemade bread and a wee box of salt. I explain that, in pioneer days, a box of salt (to scatter on the threshold to ward off evil) was a customary house-warming gift. Then a sheet of paper listing when the postman gets there, what day is trash day, and where’s the nearest liquor and drug stores.
laugh! Now that’s a tactic I could get behind!
I’ve been playing Sims2 for the last couple of weeks and I know exactly what you mean. BUT… you forgot ‘wait to be greeted, pause unconfortably for a few seconds after greeting, then insult your host’s spouse and make them cry’.
That’s always a winner. 