Paintbrush Glitch
Peculiarly enough, paintbrushes in the "Elder Scrolls: Oblivion" have no physics applied to them, and as such when they are moved out of the inventory they can be placed in midair and jumped up upon. This is because they are surrounded by a small invisible area that can be walked upon. Using this method, you can stack multiple paintbrushes like a staircase, and then access high places, such as the top of the Imperial Palace. Be aware, however, that the technique is not easy to pull off as the surface area of the paintbrush is slight and it is easy to fall off.
Infinite Arrow Glitch
There is a cheat in "Oblivion" you can use to acquire infinite arrows. Travel to any area of the game -- preferably an enclosed area, such as the Fighter's Guild basement -- and take out any bow and fit it with a set of arrows. To employ this cheat, you should have achieved the rank of journeyman of acrobatics. Knock an arrow by holding "R," then hold "L," press "Y" and move in any direction to execute a combat roll. Releasing "R" during the roll, let fly the arrow. Access your inventory and notice that the shot has not decreased the number of arrows in your inventory. Pick up the fired arrow and repeat to acquire as many arrows as you wish.
Duplicate Item Cheat
The duplicate item cheat in "Elder Scrolls: Oblivion" is usable post-patch. To employ the cheat, acquire and equip at least two scrolls. Then click on the scrolls and drop the item on the ground desired to be duplicated. The number of items you wish to be duplicated must be less than the number of scrolls. For instance, if you wish to duplicate seven items, you must possess eight scrolls. Exit the inventory screen, and the duplicates will drop to the ground. This process can then be repeated for other items without un-equipping and re-equipping the scrolls. Note that this method does not work for stolen items and some rare quest items.
Infinite Money Glitch
There is an infinite money glitch in the "Elder Scrolls: Oblivion" that can be exploited during the Cure for Vampire quest. After completing the quest, talk to the Count of Skingrad about a reward, and he will give you a thousand gold pieces. Talk to the Count a second time, and he will again reward you with a thousand gold pieces. You can repeat the conversation as many times as you please, and the outcome will be the same. After finishing talking to the Count, however, he will return upstairs to his chambers and bar the door, ending any opportunity to continue exploiting this glitch.