[quote="Neo Rasa"]The Dreamcast Smash Pack had Flicky, Sega Swirl and several other games, the PC Smash Packs were something of a completely seperate line that had been released/recompiled/etc. throughout the mid nineties and up.

What? The two PC Sega Smash Packs used a special version of the commonly-available Kega emulator. This is well documented. (I think there's even a reference to it that can be seen in the emulator code.)

I'm not sure if the same was done for Sonic & Knuckles, the Sega Puzzle Pack (Mean Bean Machine + Columns + Lose Your Marbles), Garfield: Caught in the Act, or Sonic 3D. Certainly, Comix Zone was recompiled.

If you look around now there's even ones that pack together every 2D Sonic game up to Knuckles Chaotix for not too much.
Sega Smash Pack 2 (including Sonic 2), Sonic & Knuckles Collection, Sonic CD, and Sonic R. That is all: No Sonic 1 or Knuckles Chaotix (or Sonic 3D, for that matter).