Suggetions for new mechanics
Not sure if everything is possible, but, here's a list of ideas for new mechanics:
-Glass cube (breaks if dropped from too high)
-Gel grenade (grenade that squirts out gel when player drops it on the floor)
-128 Sentry turret (cylinderic turret that can't be picked up and fits in a 128 square).
-Gel container cubes
-Personality core turret (personality core that moves on a track and shoots the player, not to confuse with the hover turret).
-Bubble Blower (big object that blows big bubbles that could carry players and objects like the excursion funnel, but pops when they touch a wall and could be moved around with excursion funnels).
Some of these are clearly obvious, but some of them are quite complex or whatever the right word is to use on mechanics that require a bit of work on them. Add what you think should be added in the thread if you want.
I liked this one. I think it would fit very nicely in fling puzzles, including momentum and the Aerial Faith Plate.
Look up prop_glass_futbol and prop_glass_futbol_spawner.
Those break when they touch the floor. The glass cube would break if dropped from too high.
Wait.. what?
Wait.. what?
It's a bit hard to understand without seeing it (if it turns out you don't understand).
I think he means something like this: http://www.youtube.com/watch?v=elayEWmXUlE.
I think he means something like this: http://i.imgur.com/w2FXDIW.png
PortalStories.com
"Oh, in case you got covered in that repulsion gel, here's some advice the lab boys gave me: DO NOT get covered in the repulsion gel."
For that bubble mechanic:Why not use fans that blows you away instead of using the funnel?
Sort of like Pnematic Diversity Vents, but it blows instead of sucking.
Sorry, couldn't resist. 
Anyway, another idea is to have sticky boxes that other boxes can attach to in certain spots, forming a bridge, a long arm to take out turrets with, or more.
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