Boskone was the first con I ever went to and the one I've gone to most regularly, though I haven't gone since I crossed the line from "fan and aspiring writer" to "aspiring writer with good reputation and enough pro contacts to crash the SFWA suite" and I'm not sure how it'll hold up now.

Aiming to go this year if I have the money, but I probably won't know until the last minute whether or not I've got the money.