While ago (at a time it was original) in 2003 I had a little game idea involving sneak&hide gameplay. The goal is to pass through the level unnoticed by security cameras. The game goes together with "level editor" (just edit levels in text file).

• Use arrows to move around
  
• You can switch some camera rotation direction once (LMB or number)
  
• ESC to quit

Explore various strange metrics (euclidean and taxi are the most well known).
The idea is some points in space acts as portals. There are two-way, one-way, two-point and multi-segment portals.

• Move your mouse around
  
• Press F1..F12 to change metrics
  
• ESC to quit

What if windows would not overlap?! The main idea behind my funky GUI test is zoom-out key, that shows multiple desktops layout and give a clue about your workspace that is infinite plane in two-dimensional space.

• Click RMB (right mouse button) to toggle between normal and zoom-out mode
  
• In zoom-out mode, hold LMB (left mouse button) to scroll or move windows
  

You are building and walking through the worlds, that can't exist in our reality. Infinite corridors or columns that are very long at one side and very short when looking at opposite side. All this stuff is possible using my simple raycaster engine with portals.

My little, old app that recognizes mouse gestures. The idea is to filter mouse input and compare gesture patterns with a record of mouse movement directions.

• Inside "writting area" you can see how to draw various english letters
  
• Small dot in every letter picture is a starting point of drawing (indicates direction)
  
• Hold LMB (left mouse button) at "writting area" and move your mouse to draw a letter