MMOs.. The only one that was ever worthwhile was Ultima Online. Vendetta Online was worthwhile but only for about 9 months.
After trying out just about every single MMO/MMORPG out there, I can safely say that UO by far surpassed anything else out there now or ever existed before.
I got into it as a way to keep in touch with my uncle, we played together while I was in middle school, and my brother picked it up not long after. It was fun for the 8 years I played it but my interest waned as the game changed too much from content addition after content addition.
Now I've been playing Left 4 Dead with my brother and sister, another great way to keep in touch while living in 3 different parts of the country.