Beat The Retreat: Songs By Richard Thompson (1994). This is a pretty fun tribute album. Best track: Dinosaur Jr. - "I Misunderstood." I can't find a copy of that, though, so here's a close runner-up.
Before Night Falls: Original Motion Picture Soundtrack (2001). Pretty pleasant music, I guess. I'm not so knowledgeable about Latin music.
Beg Scream and Shout!: The Big Ol' Box of 60s Soul (1961-69). Well-named. Six discs of 60s soul music with no clear rhyme or reason for the selection or tracklist. I don't have the liner notes, so maybe they would clear this up a bit. All awesome.
Believer 25th Issue Compilation (2005). This one has indie-rock bands covering other indie rock bands. Best track: Spoon doing Yo La Tengo's "Decora."
Believer Music Issue, July/August 2008. This one's all over the place and not in a good way. The Madlib and Aceyalone tracks are good, though.
The Best American Nonrequired Reading 2002. Buncha authors reading from their own work, curated by Dave Eggers. There's some good writing on here (Sam Lipsyte, Sara Corbett, Eric Schlosser), but it's like a serious of This American Life Act IVs.
The Best Of Blue Note (1958-65). No idea where I got this one! The tracks are great - Herbie Hancock's "Maiden Voyage," Horace Silver's "Song For My Father," among other greats, you know - but the selection is disjointed.
The Best of Mountain Stage Live, Vol. 3 (1992). I only have a couple of tracks from this one, actually: Yo La Tengo doing an acoustic version of "Lewis" and Jo-El Sonnier covering Richard Thompson's "Tear Stained Letter," but both are excellent. This is not the same version, but it'll do.
Better Than The Beatles: A Tribute To The Shaggs (2002). Not too bad, as far as tribute albums go. Deerhoof is an obvious inclusion, but the Danielson Famile and R. Stevie Moore nods are inspired.
The Big Beat 1963. All Brian Wilson projects. Best track: The Honeys - "Little Dirt Bike."
The Big Lebowski Original Motion Picture Soundtrack (1998). I picked this up for a read-through of The Two Gentlemen of Lebowski at my house a few years back. Solid selection, curated - I assume - by T-Bone Burnett, although it leaves off a number of songs from the movie.
Black and Proud: The Soul of the Black Panther Era, Vol. I and II (1968-2001). The first one mixes obscurities with soul classics from 1969-75, and it is excellent. The second one throws in some hip-hop and a Galactic track from the 00s, and I don't know what the hell they were thinking.
The Blasting Concept, Vol. 2 (1986). Top-notch SST comp.
Bloodshot Records Free Label Samper 2007: Yr Welcome, World. Okay.
Bloodshot Records eMusic Honky-Tonk Compilation (2007). Best track: Robbie Fulks and Kelly Willis on "Parallel Bars."
Bloodshot Records Sampler 2012. Even stronger. This comp sold me on Lydia Loveless, who stands her own with the likes of Dexter Romweber, the Waco Brothers, Kelly Hogan, Graham Parker, and Alejandro Escovado.
Blue Note: The Lost Grooves 67-70. Jazz-funk with Grant Green, Stanley Turrentine, and Lou Donaldson.
Blues Legends (1947-82). Well-curated cheapo blues comp. Wins by starting with a Gatemouth Brown track.
Blues Masters: Essential Blues Collection (1927-67). I don't know how essential it is, but there's some solid choices here, too.
The Bottle Let Me Down: Songs For Bumpy Wagon Rides (2002). I think this is Bloodshot doing music for kids, but Robbie Fulks wins again with his creeptastic, kid-unfriendly song "Godfrey."
Brain In A Box (throughout the 20th century). Bizarro box set collecting theme music from sci-fi movies and tv shows along with a disc of incidental music and two discs of sci-fi songs. Fun listen, but weirdly curated.
The Bridge: A Tribute To Neil Young (1989). This is a really great comp. Best track: The Pixies doing "Winterlong."