But you already knew that.
What Space Invaders made famous, the Dreamcast perfected. The sad thing is, as good as the American public got it they missed out on about 70% of the best the genre has to offer. Why you say? Up until very recently the Japanese have been releasing games to the DC, mostly in the form of some of the best shooters I've ever played.
The Dreamcast's American lineup included these gems.
Mars Matrix
Giga Wing 1 & 2
Gunbird 2
Zero Gunner 2
plus the not-really-2-D-shooters-but-are-awesome-and-share-the-same-spirit sort of games like
Cannon Spike
Bangai-O
The Japanese continue to add to their own lineup, and a friend and I have been importing most of these gems, finding little disappointment along the way.
Ikaruga (you may have seen it on the GC. Possibly the best shooter ever made)
Border Down
Psyvariar 2: The Will to Fabricate
Trizeal
Under Defeat
Chaos Field
The day of the 2-D shooters may have come and gone, but will live forever on the Dreamcast.
Later
so wait, sega of japan is still making dreamcast games?
Not necessarily Sega of Japan (hasn't released a game since 2004), but third parties have been making games almost continuously until earlier this year, at least. Last Hope, Trigger Heart Exelica, and Karous (all shooters, mind you) were games that came out early in 2007. As of right now I don't know of any more in production, but it wouldn't suprise me. Sega even started selling DC's in Japan in 2006 through their online store to satisfy both the new games coming out as well as the cult following the system has received. However, it's really hard to say games are still being developed for the system, as pretty much 99% of the content is either an arcade adaptation or a port from another system, hence the focus on the easily adaptable shooter and fighter genres. For shooter junkies like me, though, this is a dream come true, so as shooters die out in American arcades (or American arcades themselves die out) I can get my fix for awesome straight from Japan, where they're crazy about these games. I haven't had a bad import yet, and I get to enjoy my favorite genre on really the only system friendly to such games.
Viva DC!
Later
I saw a video of 'Mars Matrix' that made it look really good. I need to get a hold of this one.
I can confirm that 'Border Down' is fun, and 'Ikaruga' is quite simply the greatest scrolling shooter ever made in the history of ever (released in America on GameCube as an identical version).
They should sell game licenses to third parties so they can continue to make games for the DC (just simple games not major franchises)