All right. This is my area.

First the basics:
http://www.bodybuilding.com/fun/work...rcount=13&s2r=
2nd:

Do alot of pull-ups, and dips. Go to a playground, you'll be able to perform them. Doing both will cover your entire upper body.

3rd:

Yoga. Especially when you aren't going to be using weights, it's great because you are your own weight to stabilize yourself. It's great for your flexibility, but also for maintaining your strength.

Shit I forgot lower body.

Bike up alot of hills. Put any old shit in a sled, build a harness, and drag it. Do squats, and lunges. Even without weights, you'll benefit from doing these.

Yeah, that's pretty much it. There's so much you can do. Is there anything specific you want out of your work-out?