Nothing in-game, really. Part of the fun of the beginning of RPGs is struggling to get going. Free bonus junk that gives you a leg up..... kind of messes with that.
(It's part of the reason I specifically avoided all the New Vegas preorder items. Didn't want any of them cluttering up my game.)
...and then there were the Mass Effect 2 and Dragon Age 1 bonuses, which svcked. (ME2 armor was ugly and didn't work with the regular armor system; DA armor couldn't be used until you'd leveled a whole lot and stacked plenty of Strength - until then, it just svcked up valuable inventory space.)