Origin Point is a mouse oriented, sidescrolling, 2-D platformer that had previously been frozen in terms of development but has been revived. There are currently two demos available, though much more is planned. Its homesite is located here.
Demo 2 Screenshots
Controls
Movement: W A S D
Aiming: Mouse
Fire Selected Weapon: Left Click
Lock-on to Enemy: Right Click
Change Weapons: Mouse Wheel or E and F
Pause: Space