Renting Mobile Hotspots

Anyone have any experience renting a 3G/4G mobile hotspot in NYC?

All I’ve turned up so far is a place called Xcom (not the game) that is in the business of renting hotspots to international travelers for $15/day.

I only need this for an event in NYC so I’m not all that interested in getting into a long term contract with Verizon/ATT/Sprint although month to month would work.

Thoughts, advice?