I've been hearing some of you going ape over some of its games like Xenoblade Chronicles, which I would really love to play. And I have found a place to get the black motion plus bundle real cheap. Also, its modding is extremely easy and versatile from what I've seen - just strap an external HDD onto it and you're good to go.
I paid 135 Euros for my Black Wii. Then you need a 2 GB SD cart (for modding) and a HDD. If you like it oldschool, you should get a Classic Controller Pro, too.
It's really worth the money. Modding takes about an hour, and then you're done.
Yess, that's cool. If you like to use the NES, SNES and Genesis emulators, you'll need the CCPro. This emulators are really good (the GBA emulator is good, too).
I got a black Western Digital Passort 500 GB (50 Euros), but that's almost too small for me now. I'd buy 1 TB now, but that's not really important. You can always buy a larger HDD in a year. Or two.
You can watch all your AVI movies with your modded Wii from HDD, too. This alone would be worth the cash, imho.
If you have a normal (--> old) TV like me, then a Wii is enough. More is not possible. And you have a really big libary of games. I spend most of my time with WiiMC (the AVI player) and the SNES emulator now.