Donkey Kong 64/Frantic Factory

The C-up glitch can be used to get through the hatch to the left of the entrance without hitting the switch. Video
DK can reach the platform with the power shed without dropping to it from the R&D room. Use the climb up slippery slopes trick to reach the switch that Lanky hits to free Chunky. Then do a kickjump combo to get to the platform with the shed.
Diddy can also reach the power shed platform with dropping down to it. The easiest way to do this is to backflip onto the edge of the door closest to Diddy's switch in the Storage Room. You will probably fall off, but hopefully you will be able to backflip in midair as if you were performing the trick to climb up slippery slopes. If so, backflip to the top of the door, then jump up to the switch. Video (#2)
Lanky can get to his bonus barrel in the Testing Room without Baboon Balloon. Jump on top of the nearby door, then high jump to the bonus barrel. Video (#2)
You can get out of bounds by using the C-up glitch on the hole in the floor near the Battle Crown pad (not the one with the Battle Crown pad in it). Video
Chunky can turn into Hunky Chunky before the fight with the giant toy monster starts if he is standing in the right place when the cutscene showing the monster assembling itself begins. The monster is invincible for a while, so Chunky has a chance to grab the bananas in the room as Hunky Chunky. Video (#3)