There are lots of amazing punk bands from the late 1970’s that are completely unknown, but IMHO, the greatest is The Urinals - they only released 3 singles, but they were all unique, wild and totally different from each other. They have a very good compilation out on Amphetamine Reptile called ‘Negative Capability’ if you don’t want to spend $100 each for their records. Yo La Tengo have also covered two songs of theirs (Surfin’ with the Shah and Black Hole).
HenrySpencer
SaxFace -
Who do you know in The Pilfers? I’ve got Chawalaleng playing right now; it kicks ass. The Pietasters (ska) rock as well, and the The Bouncing Souls are a quality punk band from NYC.
SwimmingRiddles -
I’ll back you up on Zola Turn, but I’m not a big viperHouse fan. Strangefolk is always quality - Garden of Eden is coming up soon. Rustic Overtones provide some decent tunes as well.
I’ll offer Billy Bragg, on the qualification that none of my friends have ever heard of him.
-ellis
One of my favorite unknown bands is GIANT. They have 2 albums out… one called “Time To Burn” and another called “The Last Of The Runaways” hence my username.
Other ‘unknown’ bands, or musicians, that deserve more credit than they get:
Tony MacAlpine
Stratovarius
Edguy
House Of Lords
Racer X
The Storm
Ten
Hurricane
Rough Cutt
theres probably more.
Yeah! A fine list all around. And not just because you mentioned Guster. I really wish Orbit would get more radio play, sweet guys, good band. Even if the lead singer would make a pretty girl.
Dude, you need new friends. 
I’m not too much into the prog jazz viperhouse thing, either, but that chick has a GREAT voice. There’s also a band around Burlington named the Currently Nameless, I’ve never heard them, but they get the best band name award.
Ellis555 said:
I know Nick Bacon, the guitarist - he’s a great pool player.
If you give me $20 I’ll tell you where he lives.
From the Dallas area:
Ten Hands (now defunct)
Green Romance Orchestra
Anybody ever heard of them?
SaxFace said
I’ve got some buddies who might take you up on that. Chances are, though, they’ve already hung out with him at a show.
SwimmingRiddles -
Who’re you kidding? The Tragically Hip have the best band name ever. I’ve heard of Currently Nameless, but I haven’t heard them.
-ellis
Not entirely unknown, but very little known:
Red Snapper
The Tindersticks
Someone already mentioned
Alice Donut
And not completely unknown,
Cibo Matto
Windy Austin and the Hothouse Tomato Boys - Been around Little Rock for years.
Another one that use to come though occasionally is Billy Goat
Haven’t seen Joe Savage in years. The last time I caught his act, he was playing a lounge in Reno.
I’ve heard of dada, Old 97’s(wooo!), Muckafurgason(woooo!), Tea Party, Modest Mouse, Three Alarm Fire, The Inbreds, Oingo Boingo,The Red Elvises, The Urinals, Billy Bragg!, STONE ROSES, The Silos, Mars Electric, Superdrag!, Racer X so a few of the bands listed.
Anyone know of Macha, or Bedhead(from my town)? 2 Skinee J’s, Super Furry Animals(Wales), Tripping Daisy(Dallas), Mercury Rev(pretty well-known) The Longpigs(England), Robyn Hitchcock, Bigloo(local), John Lurey and the Lounge Lizards, Tom Ze, Stereophonics(England), so many more…
Here’s just a few from my own collection:
XTC - most overlooked band in the history of ever
Nathalie Archangel - One nifty album, then nuthin’
Switchblade Symphony - Serpentine Gallery is great stuff
Magnetic Fields - 69 Love songs, an act of hubris that lives up to its concept
Beautiful South - Bitter bitter bitter lyrics over some of the most cheerful pop songs you’ve ever heard. British band I understand is quite well known there.
EAV - Actually an Austrian band, whose name translates into something like “First National Endangerment Company”. Like a cross between They Might be Giants and Depeche Mode. But only sorta.
Voice of the Beehive - two GREAT albums, one merely good. Buy all three and find out which!
John Wesley Harding - Like a cross between Elvis Costello and Bob Dylan only really really good. And funnier than heck live.
Pulp - Yet another fey british band no-one in the states is likely to have ever heard.
The Ukrainians - did an ep of Smiths covers using Ukrainian folk instruments that has to be heard to be believed.
Hmm. That’s a lot more than I thought I could think of off the top of my head. Maybe I’ll grab some more when I get home this evening.
XTC and Pulp, both very good. Everyone should also know who Suede(London Suede) are.
As far as punk groups, everyone should also know Screeching Weasel. Classic songs.
Moxy Fruvous!
There’s also a very funny band local to Boston called Honest Bob and the Factory-to-Dealer Incentives that I recommend.
Anyone know about Shivaree? They’re really cool.