Regarding the Cheats & Hints.
Hi there,
In Oblivion the developers left in a load of "testing cells" which contained; basically every item in the game, as well as lots of things to test with (doors, locks, people, etc.). For me it was far better to equip my character without using the player.additem code and a long list of hex codes.
After going through the fallout3.esm with a hex-editor, I believe I've found the name of at least one. The one containing all of the items in the game.
Open up the console and type.
coc TestQAItemsIt seems that they've named the testing cells with a prefix of "TestQA" this time, I haven't found the testinghall type cell that was in Oblivion which linked these together. To get back to the other cell that you was in will be a little tricky; I remember there was a cheat/debug command in Oblivion that gave you the name of the cell you was in, perhaps thats the same in Fallout3. You find out that and you can get back.
At least this will be very helpful for those who are working on the additem lists.
Enjoy!
--Edit--
I've found a way to get back, you can warp back to the Megaton Common House via:
coc MegatonCommonHouseHowever; If you did the quest with Mr Burke, then it should end up with some interesting results.
[Edited by trandy, 11/2/2008 3:04:37 AM]