I have seen a few of these popping up, and the results have been very interesting, so Im here to do my own :D
My level difficulty rankings may be odd, please notify me if you spot anything you think needs changing.
Easy:
http://www.fantasticcontraption.com/?levelId=571215 - Speed Challenge
An easy level, but try to complete as fast as you can.
Current record:
http://www.fantasticcontraption.com/?designId=11301498 - Zac Z - 27 ticks
http://www.fantasticcontraption.com/?levelId=569299 - Straight N True
Try to fire the ball through the tube
0wnyouu: http://www.fantasticcontraption.com/?designId=11414982
http://www.fantasticcontraption.com/?levelId=570510 - Slot 2
Get it in that slot quick!
Medium:
http://www.fantasticcontraption.com/?levelId=572858 - Gymnastique 1
French for 'Gymnastics'
http://www.fantasticcontraption.com/?levelId=573693 - Gymnastique 3
http://www.fantasticcontraption.com/?levelId=573247 - Lervia
Dont ask where I got this name :P
Tough:
http://www.fantasticcontraption.com/?levelId=575208 - San Jose
Get that last Chilean miner out!
Rianbay812: http://www.fantasticcontraption.com/?designId=11400747
http://www.fantasticcontraption.com/?levelId=576972 - Call Center 2
Have fun with this one!
Harder:
http://www.fantasticcontraption.com/?levelId=577320 - Database
The hardest level I have right now
uuuiiiooop: http://www.fantasticcontraption.com/?designId=11414507
Will add more levels here as I make them.
Have fun!