if your goal is strength, agility, balance, endurance...
parkour-search for the vids on youtube. using the outdoors as your "gym". If you have a buddy to workout with. this activity speaks for itself especially if you like being outdoors.
go to the second hand shop-you'll be able to get a bench and most likely all the weights you'll ever need. you'd be surprized what people donate or throw away. check out your local buy and sell, flea markets etc
one sports store where I live had a weight set
(300 lbs and olympic bar) for $109.
are you close to an open area? run-wind sprints etc, plyometrics. go to your local school.
cycle, hike, skip rope
exercise ball, as suggested above $7 or $8 at wallyworld. an excellent piece of equipment.
all sorts of good videos on youtube etc for home workouts.