PowerlessCamp - no power. no lights, no laptops, no projectors. no wifi, no video or audio recording or amplification. Held outside maybe, in daylight. Maybe with some picnic benches.
virtual code4libcon - the regular conference is capped to fit a single track, which is lovely, but there are probably at least 2x-3x as many people who cannot attend. Those who don't attend but want to present and see other presentations post 5 minute lightning talking head or slide videos with a shared tag to an agreed-upon video sharing site before the start of the physical event. Then people at the conf can arrange a time/space to hear from those not present, and people not at the conf can hear from each other, and there's no hard limit on participation.
42camp -
AntiFest - the only accepted talks are about what you've done wrong in the past. could be held in conjunction with
Speaker For the Dead Code Camp - where you do what Ender did [1], but for code you no longer run.
Links:
[1] http://en.wikipedia.org/wiki/Speaker_for_the_Dead#Meaning_of_the_term_.22Speaker_for_the_Dead.22