i stombled oppon a glitch infallout new vagas were u can get 35 xp over and over again till u leave to find. first you will need 40 points on speech and sciance so make shour you have that. next you will need to do the main quest all the way to were ur invited into the luky 38 casino were u meet mr.house ask all the questions u can untill u one has science or speech ask it to recive 35 xp. once done u can go back to ask it again and recive 35xp again. repeat this as much as you want or till u get tired.

WARNING: if you leave and do the mission it wont work anymore.