I think Satchmo wins the thread
I can name a whole host of albums that I've checked out because it seemed "cool" on Musicbanter or RYM. I'd say about 25% of the time I delete the ones I dislike after a spin, and the other 75% I hang onto in the vain hope of "understanding" them one day. Such as
In the Aeroplane over the Sea
VU and Nico
A Love Supreme
Rain Dogs
Ágætis byrjun
etc