An interesting wine tidbit that has been getting some good press lately (e.g., see this article at the Washington Post), is The Wine Century Club. The club doesn't have many members (somewhere in the low hundreds), and it hasn't been around that long (about a year and a half). But it's got spirit, boy! And it's the kind of venture that sums up everything I love about wine.
There are 1,000+ different grape varieties being made into wine, and that is in one country (Italy) alone. The full list is probably not known. And though most of the grapes being made into wine these days are thought to come from one progenitor (the Muscat of Alexandria grape), you could taste wine for a lifetime and never get bored.
The fine folks at The Wine Century Club understand this, and their group is devoted to exploring the fun of trying wines made from uncommon varietals. To become a member, you download their application and mark which wine varietals you've tried; when you reach 100, you're in. Simple as that.
But it's not really that simple - a staggeringly low percentage of those who have downloaded the application actually send in a completed copy. It's not that easy to try 100+ wine varietals - thank god that blends count (so one blended wine means you've tried all of the wines in that blend - congratulations).
Between all of the formal and informal tastings I've been part of, my own penchant for trying new things and new wines over the years, and my prep. work for the WSET exam, I've been able to reach 100 (over actually, but I stopped at 100 because the piles of tasting notes I needed to reference to check which varietals I've tried were beginning to overwhelm my desk). I faxed my application in today, baby!
I'm not sure what I'll get once my application has been accepted - except for bragging rights, of course. But you could spend your time in many worse ways than downloading the Wine Century Club application and starting to work your way through the varied and fun world of really uncommon wine.
And though it will usually get you two checks on the application, I recommend against trying Retsina... :-P