We started making USB sticks with Vagrant + VirtualBox + git bundles on them for the Zürich hackthon to help make installing easier and to save many gigs of conference wifi downloads.
Having 15-20 USB sticks with the software pre-installed by the start of the first day of the hackathon would be optimal. We could probably get by with as few as 5 if needed as the easiest way to use the sticks is to copy the data off to the laptop's local hard drive before installing. Each new user only needs a stick for 5-10 minutes to accomplish this usually.
There is a host in Labs that can be used to prep the base image which then just needs to be copied on to the sticks. The install image is ~2.5G so 4G USB sticks are more than large enough.