Here's the older game I was thinking of, http://www.ravensoft.com/tnp.html. There a link to the demo there.

If it was done well, I would play the game and love it.

Have you guys ever played Soldat? It's a 2D shooter that plays online, and is incredibly fun... although not many players play it now. The way it works though is amazing, like you aim with your mouse, while still walking left/right or jumping, and it had a little 'boost' shoes that let you fly upwards for a few seconds. If you are trying to figure out how to make UNREAL 2D work, I suggest giving Soldat a try for some ideas.