Thank you for posting these.

I love these types of puzzles and questions.

I'm not reading others responses, I'm just winging it... first guesses... Here goes:
1) You are stuck on top of a building, you have a chronometer and an altimeter. How do you find the height of the building?
Let's see, you could drop the altimeter off the top of the building and time it's fall to the ground with the watch. If you know the terminal velocity of the altimeter, you could then calculate how tall the building is.

2) You are outside a room facing three switches. Inside the room is a light bulb. One of the switches is connected to the light bulb in the room, two lead somewhere else. All three are in the off position. You are allowed to enter the room only once and once inside the room you cannot leave it. How do you find out which of the 3 switches controls the light inside the room?
OK...
1) Turn the first switch on and leave it on a good minute or more. If it's THE one, it will light the bulb and heat it up.
2) Turn the first switch off and the second switch on and enter the room.
3) If the light is on, well, it's obvious, the second switch controls it. If the light is off but warm, the first switch controls it. If the switch is off and cold, the third switch controls it, and your stuck sitting in a dark room thinking about Swoop's next Wednesday's Babe until someone lets you out. Pretty sure I got this one, yeah?

3) I am the beginning of eternity, the end of every rhyme. The begging of the end and the end of space and time. What am I?
On acid?

I fail.

Was fun!~
Checking my answers with the others now.

Stalwart