Green tea, red bean, ginger, and lemon sorbet. I can't take vanilla, it's just way too sweet, I'd rather drink yogurt. The ice cream from those Gelatin (sp?) stores in Italy when I went there this summer are good also, but a bit too sweet.
I recently tried that Bailey's flavored Ice Cream, Dreyers or something I think. It was good. But favorite? Well, that's tough. Since most of my favorite Ice Creams are vanilla based, I'll just go with Vanilla.
You should try it. I make green tea ice cream all the time. It is more delicious than you might think. I also recommend avocado-pear.
It's one of the few ice cream flavours that does not make you get sick of it after eating it everyday. Personally I just think it tastes better than most flavours found in places like Walmart (vanilla, chocolate, strawberry, etc). Unfortunately it is also usually twice the price of the other flavours, maybe bit more healthy or harder to make?
If you're ever in San Francisco... http://biritecreamery.com/: salted caramel, coffee toffee and cookies & cream are really good, or, there's: http://www.humphryslocombe.com: blue bottle vietnamese coffee and secret breakfast (corn flakes and bourbon) are good picks too. If not, Ben & Jerry's Cherry Garcia is good too.