I interviewed for a NYC startup who told me their perks are free groceries from an online grocer, an office kitchen with nice appliances, and he has no problem with me bringing a sleeping bag to the office (and save a fortune on rent while living in midtown). He said its probably an option if you are single(he said don't tell me though for obvious reasons). Each office is a 10x10 room that can be closed off for privacy.
There is also a free gym membership where a shower is available, a new laptop under $1000, and 20 free iTunes every week. The salary offer was 30K with equity. This is something I would be interested in doing, especially since I could crash in the office. I think it's a great idea because I can spend many uninterrupted hours working. I hated commuting home after a long day.
I notice though that some startups offer some amazing perks like free meals created by chefs and massages. There is nothing even close to that in the average corporate job.