When I was in high school at some point, I came across a shareware version of a game called Tyrian that was basically a topdown shooter in outer space, with a story, over-the-top enemies, and terrific customization options.  I played it not too long after I first tried Raptor (a very similar game that was itself pretty popular at the time), and I thought Tyrian blew it away.  At the time I didn't have much money, so I didn't actually unlock the full game, but I must have beaten the first mission a dozen times on the shareware version.  I loved it.  Recently, I found out that a more recent version (Tyrian 2000) is being distributed online and can be played via DOSBox, so I gave it a shot again.  The graphics obviously have taken a hit, but they were very good at the time and certainly still playable.  The story isn't quite as cool as I remember, but the gameplay is still very solid.  Tyrian does a great job of putting a ton of enemies and bullets on the screen at one time, which makes for really frenetic gameplay.  Anyway, if anyone's interested, DOSBox can be found here and Tyrian 2000 here.

When I was in high school at some point, I came across a shareware version of a game called Tyrian that was basically a topdown shooter in outer space, with a story, over-the-top enemies, and terrific customization options.  I played it not too long after I first tried Raptor (a very similar game that was itself pretty popular at the time), and I thought Tyrian blew it away.  At the time I didn't have much money, so I didn't actually unlock the full game, but I must have beaten the first mission a dozen times on the shareware version.  I loved it.  Recently, I found out that a more recent version (Tyrian 2000) is being distributed online and can be played via DOSBox, so I gave it a shot again.  The graphics obviously have taken a hit, but they were very good at the time and certainly still playable.  The story isn't quite as cool as I remember, but the gameplay is still very solid.  Tyrian does a great job of putting a ton of enemies and bullets on the screen at one time, which makes for really frenetic gameplay.  Anyway, if anyone's interested, DOSBox can be found here and Tyrian 2000 here.

I've played Raptor too.  Never heard about Tyrian or Tyrian 2000. 
  
Nice find! Thanks!

There's also now OpenTyrian which has been ported to Wii and XBOX.

Ohh, excellent :)