Animated Jazz Covers. Very cool.
Dirtbombs' drummer Ben Blackwell has created a map of Detroit of labels offering "vinyl releases throughout all eras". He also has a blog and participated in the SXSW panel "How to Make Money With Vinyl" (mp3) as an employee of Third Man Records.
Vintage Vanguard is a Japanese web site featuring the cover art for every Blue Note album ever released. Other labels are featured as well.