This weeks Spare Time Flash Assassin is Portal: the Flash Version from We Create Stuff. As the name implies, it's a flash game based on Valve Software's critically acclaimed Portal.
Portal: the Flash Version, like the original, is a puzzle-platformer in which you create a portal by shooting the openings of the portal onto the floors or walls (I know it sounds confusing, but it's basically simple). These portals allow you to transport yourself across the rooms, thus navigating the puzzles.
It's not too bad. Click here to play it.