I 3rd the recommendation for Żubrówka. Unbelievable flavor. There's a polish restaurant in LA (Santa Monica?) that makes a killer Apple Martini with the stuff...it's not bright green. and it tastes just like an awesome apple pie.

Interestingly enough, besides LA, I've found it Sapporo, Japan.

but since I can't find it where I live, I stick with Chopin.