In terms of benefits: almost all backgrounds either give small skill bonuses, or let you base your hit points on the stat of your choice (instead of constitution). The latter group are much stronger than the former.
"I would really like to see a game made by Obryn, Kurald Galain, and Knaight from these forums. I'm not joking one bit. I would buy the hell out of that." -- ChubbyRain