[itswitch]

Doors. I would have doors open themselves, either because my phone is near the deer and my keys are nearby, or an implanted RFID chip. Or anything. Just a way for doors to open quickly and silently, to just the right amount. Not too much, not to little (it would depend on the situation).

[brwr]

Air compression is a valid solution here, if I am understanding what you're asking for. The trick would be developing a silencer for the compression tank similar to that of a firearm.

Check this out:

http://youtu.be/otYAm6OXnH8