Portal 2 (Spoilers Possible)

[Woppet*]

i know the one you're talking about two. Didn't take me long to figure it out but it took me a while to pull it off sucsessfully.

Here's the solution:
[spoiler] Coat the long runway with the red gel. If you stand on that runway and look in the opposite direction of that floating island where you found the cube, You will see a ramp you can portal too. Coat the ramp in the blue gel. (i will call this ramp ''Ramp A'' so i can refer back to it later.

Then portal over to the place with the switch and the platform that flips when you step on said switch. While you AREN'T on the button, and the platform is still upside down, create a portal underneath it and use it to coat the platform with blue gel.

THEN, place the the cube on the switch so the platform turns the right way up and portal back to the runway.

Nearly there now. Place one portal at the end of the runway, and the other on the wall facing 'Ramp A'

Run down the runway into the portal building up speed. You'll bounce over and land on the flipping platform you put blue gel on. You'll still have all that momentum so you'll bounce again and land on the platform that leads to the exit.

I realise you've probably already figured it out by now. [/spoiler]