[quote name='javeryh']Nice post. What are some of your favorite arcade Shmups? I'm always looking for something new to try out. I just discovered Don Don Pachi and I love it...[/QUOTE]
As far as modern (32-bit+) shmups go, most people will tell you to get
(Do)DonPachi
Batsugun
Battle Garegga
Radiant Silvergun
Ikaruga
Psyvariar Revision
I also really like (some "purists" will disagree)
Layer Section aka Galactic Attack
Border Down
Hyper Duel
Soukyugorentai (Otokuyo) aka Terra Diver
Cotton 2/Cotton Boomerang
Homura
most of these are japan-only saturn games. some are quite expensive, but a few can be had for 10-20 bucks on ebay. a saturn with an import cart shouldn't run much more than 55. if you had 125 or so to spend, you could probably get the machine, Galactic Attack, Batsugun, Donpachi, and Soukyugorentai. of course, that doesn't include a joystick....you can find adapters at liksang.com for ps2->saturn. please don't upset the shooting gods and try to play these games with a pad.
if you are looking for some domestic Playstation 2-compatible releases, try:
Thunder Force V
Raystorm / Raycrisis
Gradius III/IV/V
R-Type Delta/Final
Strikers 1945 (actually, this is Strikers 1945 II, but not labeled as such on the US release)
Castle of Skikigami 1 & 2 (in US, a version of CS1 is known as Mobile Light Force 2)
Gunbird (in US, known as Mobile Light Force)
the nice thing about going with these is, half of them are 10 or 15 bucks these days, and the others shouldn't cost more than 25 or 30. the Mobile Light Force games have butchered sound and most story elements removed, but the gameplay is identical to the original versions AFAIK.
additionally, i believe (Do)Donpachi, Batsugun and Battle Garegga (and maybe Hyper Duel and Terra Diver) are playable via MAME......although once you get hooked on Garegga, you will want to pick up the saturn version due to the various enhancements included

there are a bunch of other good MAME-playable shmups too....check out
www.shmups.com for reviews and more recommendations.