Looking for Retro Shoot em ups

What are some good shoot em ups? I have a most of the ones I want on the SNES but I'm looking for some that might be on PSN or on a PS2 compilation disc. Is there any way to play the Aero Fighter games on PS2 or PSN or something? I'm not into emulators or anything.

PSN has some good ones:
GaiaSeed
Gradius V
Raiden IV: Overkill
Shienryu
Sonic Wings Special
Under Defeat
Zanac x Zanac

There are also several SNK and Hudson shmups on there but forget what all of them are.

The Capcom Classics Collections vol 1-2(PS2) have some good ones like 1942, Last Duel, Legendary Wings, Side Arms, and more

If you have a PSP(or Vita since it's on PSN), there is the Gradius Collection.

Konami's other collections such as Parodius and Salamander also joined the Gradius Collection on PSP. I think the Capcom Classics games on PSP had a few also from the console releases maybe. For compilations I think the 2 Gigawing Dreamcast games had an import compilation on a PS2. Do you have any other platforms such as a 360, Saturn, or Dreamcast? I'd know more on those platforms.