A keycoded room
This is my third version of a keypad. I reduced the number of entities by about 25. It has a different function, but is better for people brute forcing it.
http://www.youtube.com/watch?v=8KpY2RWvpco&fmt=18
The code can be changed in about 20 seconds, with a quick edit in hammer. I am making a tutorial for the dev wiki.
How convenient. It reminds me of a storyline quest in Fallout 3...
I won't spoiler, but anyone who played the game will know what I'm talking about.
But it looks and seems to work great. Must've been a lot of work too. Entity logics can be a real pain, but the results are often totally worth it.
"Duct Tape is the answer."
That's a cool idea. I like the way the buttons really push down. Can you also set a code that uses the same digit more than once?
BTW I'm looking forward to that tutorial.
Yeah, tell me about it...
Other Portal 2 maps: Medusa Glare
Portal 1 maps: Try Anything Twice | Manic Mechanic
Currently, no you cant reuse the same button, it is possible i suppose.
http://www.youtube.com/watch?v=_awmz7xLLmo
It can be programmed in under 30 seconds 
Ill put it on the dev wiki either tonight or tomorrow.
I was going to post my idea of making one, that could use the same number more than one time, but i saw a bug in it so i didn't. Looks awesome. Keep up the good work :3
I've been thinking about something like this for a future BTS map (where you have to find the code to a control room or whatever) and making the keypad so that it can re-use ditgits is a lot more complicated than the simple and elegant solution used here. We're talking about a video game after all, not about Fort Knox.
@sbrown:
I've watched the video where you program the keypad. The template is surely user friendly. I assume that the pk1_button_a, pk1_button_b etc. are control entities that all have to be activated for the code to be valid, am i right? How then do you enforce the right order of the digits? (So that when the code is 4862 for example, entering 2684 doesn't work.)
Other Portal 2 maps: Medusa Glare
Portal 1 maps: Try Anything Twice | Manic Mechanic
The kp1_button_a buttons are middlemen of the sorts. They can be locked to prevent the keypad from being unlocked, but still allowing the buttons to function on the outside. I guess ill write up that tutorial tonight