The following trick can be performed when you have at least a 35 Medicine skill. When your character gains access to the main strip go to the Lucky 38 casino and search for Victor who will tell you that Mr House wants to meet you. Follow Victor inside the Lucky 38 casino and go up the elevator and speak to Mr House (giant television face that resembles Howard Hughes). Select the dialogue choice pertaining to ask him a few questions and ask 'Who exactly are you, Mr. House?' followed by 'You appear to be a computer, not a man'. Then select the Medicine Skill check response, 'The lifespan you're claiming is impossible, except for ghouls and super mutants'. You will then be awarded 35 Experience Points (or 39 Experience Points if you have the Swift Learner perk). This process can be repeated as many times as desired.
Added by: Sanzano Oct 26th 2010, ID#6467