Honestly, this is reliably the hottest topic I see.  Yeah, the dearth of replies so far may belie that, so you'll have to trust me.  Every year at the National Meeting we have an open session for discussion, and this is _always_ brought up.

I'll toss one out to hopefully prime the pump and see about getting more people to respond.

Do what you do best.  Theatre.  But do it in ways that aren't quite so traditional, and are therefore cheaper.

Do spontaneous "guerrilla" theatre, and have someone involved with the show working the crowd for donations.

We used to do what we called "Theatre Slam", which was 24 straight hours that started with writing a new show, then auditioning it, casting, rehearsing, building whatever was needed to be built, and performing it.  Charge a buck or two for admission.  Generally it turned into an evening of 3 one-acts, and one time one of them was a full-blown musical.