- Edited
Level "Swap" (ID: 956) by AndyB
Swap
A solution by AndyB (Time: 2.8s, Blocks used: 9)
A solution by Tom (Time: 2.4s, Blocks used: 12)
A solution by Tom (Time: 5.4s, Blocks used: 7)
A solution by AndyB (Time: 2.3s, Blocks used: 10)
14 days later
A solution by cf (Time: 1.5s, Blocks used: +6)
Non-clipping. Faster. Fewer blocks. 
This took me a while. Did not look at the others first.
ColonelFazackerley Great solution. Almost a new technique we might use elsewhere.
Perhaps a taxonomy of techniques is worth writing.
5 months later
2 months later
A solution by niel (Time: 3.2s, Blocks used: +22)
12 days later
A solution by Stefan (Time: 1.7s, Blocks used: +18)
A solution by Jan (Time: 2.9s, Blocks used: +10)
A solution by Ralle (Time: 1.4s, Blocks used: +17)
A solution by Blotto (Time: 1.4s, Blocks used: +27)
A solution by A3 (Time: 3.8s, Blocks used: +8)
A solution by AceJay (Time: 1.9s, Blocks used: +12)
A solution (Time: 1.3s, Blocks used: +25)