Bugs

Strange Bug
Maker sure you have beaten the game on 00 Agent and have the all guns code and 007 mode(Infinate ammo helps too). Play the first surface level and play the level like normal, completing all the objectives. Once you have all but the last objective done (the one where you enter the ventilation tower) go to the helicopter landing pad. Go to the door and atempt to open it, the alarm will go off. Now switch to any of the explosive weapons and the icons for the ammo will be totally messed up, and somtimes the rocket on the rocket launcher is green!!

See Through Bug
My trick is on the first surface level.Go to the fenced in area and follow the road to the other two buildings.Go to the left building and look back and you can see a mound on your left go to the mound and get close to the wooded boundry.You should be able to see threw the wall and you can see purple guy coming from a distance, and you can shoot through it to.

Bunch of Weird Stuff
I have stumbled across a number of mysterious places in Goldeneye. I don't know the purpose of any of them, but they are there.

Dam:
All the way at the end of the level, when you reach the dam itself, climb down to the lowest level, by the docks. Get out your sniper rifle and go to the edge of either of the platforms by the water and zoom in across towards the base of the mountains in front of you. Scroll left and right until you find a tower and building toward the left.

Facility:
This is found toward the beginning of the level. Before you do it it's best to kill all the nearby gaurds upstairs and downstairs (before the remotely locked security door). Next, when you go downstairs straight from the restrooms, you will be in front of the door with the control panel inside. Turn left and go to the end of the hall, in front of a single door. Turn right and take a few steps forward, then turn left. There will be double doors in front of you. Go through them, and there are two corners in this series of hallways. At each corner, look straight up. The ceiling is high and there are vents going across the top. At one corner, there are two that criss-cross. On top of on of these is a long line of glass test-tubes and bottles that can be destroyed.

Silo:
If you kill Ourumov in time he drops a strange metal briefcase and a keycard, when looked at in your inventory is just a period.

Texture Bugs
On Surface 2 and sometimes Surface 1, trees in the back can be rendered after trees in the front, therefore putting the trees far away in front of the trees close to you. This is best shown when walking by the left wall when coming from the small place past the fenced houses and facing towards the fenced houses. This also seems to happen with semi-transparent textures, ie hand rails and rail supports. Examples are on the cradle, further fences are rendered closest, and on the facility level with toilets when looking at the stairs rails.

Floating Mine
When playing, throw a mine onto a glass surface then shoot the glass until it breaks. Strangely the mine is in midair and does not fall on the ground.