I haven’t tried building a computer in about 6 years, back then video on a motherboard was really really sucky and you needed a seperate ethernet/LAN card. Nowadays I think you can buy motherboards with good video and a build in ethernet function on them.
So what all functions do modern motherboards provide? Video, audio, LAN, and what else?
From what I have seen, most motherboard still do not have on board video. Some do, and the ones that do have better video than before, but if you do any kind of gaming, you still need an AGP (or even better, PCI-E 
) video card. Actually, the ones that most often have video are micro-ATX form factor. Since the idea behind those is to make it small to mazimize space, they realize many peoiple who buy them don’t want to have to fit a video card too, so they have onboard video.
Almost all of them have built in LAN, some even have built in gigabit LAN and a few have built in wireless. All now have built in sound, and it’s usually at least 5.1 sound. Hell, mine even has a built in optical out for my 5.1 sound. 
Some motherboards have a built in firewire port, but most of them don’t have the actual port, just pins so that you can hook up the front firewire and USB ports that most cases have nowadays.
I bought a new board a couple of months ago. Onboard it had:
2 gigabit LAN
4 USB 2.0 ports
1 firewire port
5.1 sound
RAID array supporting upto 4 drives (built in, but optional for use)
Headphone/mic jacks
Heck, the only daughter board I have in the thing is a video card.
I really, really hate people who say, “Google it.” That said, good god man, it would take less time to go into Froogle and type in Motherboard than it did to type in your OP.
Now that the ethernet (and by extension the internet) is a feature of your motherboard, why not use it in the way that God and Microsoft intended?
Let’s not give Microsoft too much credit:
– Bill Gates, 1993