Hell Fighter 32

Hell Fighter 32 is the networked version of Hell Fighter. The new interface is multiplayer centric.
Hell Fighter is a fast action game, and you'll want a good connection like DSL or cable.

It's playable on a 56k modem, but (as with other fast action games) your controls will be sluggish.
You can still play by yourself just as if it were a single player game, but others can connect and join you.