My vote as the most under-rated band of the 1990's... and probably this decade also...

eels

As of today, this wonderful band have released three reasonably low-key albums, generating a semi-reasonable amount of airplay, but barely what they rightly deserve.  This wonderful band makes you feel like they are there in your home banging away on keyboards, drums, bongos, whatever, right next to you, as you close your eyes and drift off with them...  With songs which seem to be so wonderfully studio-mixed, it is a surprising awakening to see listen to live performances and see an amazing replication - combined with improvisation - to result in wonderfully sounding tunes which make you want to cry, cringe, smile, and leave you with that warm feeling in your tummy :-)  I cannot rave enough about this band... if you cannot understand why not, simply purchase an album... any album...

And with quality b-sides and unreleased tracks, too, there simply is no excuse not to.

I think the greatest homage I can pay to eels as a band is by saying that, while Radiohead still top my mental-ranking of favourite bands, I think if I was going to be musically famous, I would rather be in a band similar to eels, since the low-key, fun, beautiful, breathtaking sound is a style which no one can match.  If your favourite band compares to the greatest day of your life, eels is my quiet Sunday when I went for a swim, finished a book I loved, and fell asleep in the arms of the woman I love.

fond, but not in love?

I actually finished ranting, but I thought of something to add when I went and lay down on my bed... other bands have their time in the sun, and their fans die out when they go out of fashion (ie, anything commercial)... others have their cult followings (Radiohead certainly, and many other freakishly good bands)... but eels fans are amazingly pensive... with Radiohead fans, you just know when there's a freaky Radiohead fan, because it's a maniacal look in the eye which gives it away... with an eels fan, you can know someone for months and not know... then, one day, you'll casually mention eels, and they'll look at you, and you both smile because you feel the connection, and when your eyes meet, they say, "you too?"  And you say, "yeah".  And that's it.  A secret society of sorts.