My sorting system:

1xX Bricks
2xX Bricks
Modified Bricks
1xX/2xX Plates
3xX/Bigger Plates
Modified Plates
Slopes
Round Bricks/Plates
Technic
Technic Bricks/Plates
Wheels
Windows/Glass
Doors/Chairs/Chests
Plants
Tiles
Hinges/Turntables
Misc
Big Roof/Wall Pieces
Flags/Poles
Baseplates
Soccer Field Sections
Minifig:
   Heads
   Torsos
   Legs
   Headgear/Hair
   Neckgear
   Weapons/Accessories
   Animals
   Canoes/Motorbikes
MegaBlocks/Clones
Unsorted