Vacuum sealing is useful for all sorts of things, but if you don't feel like shelling out for the pricier vaccum seal bags, you can get by pretty easily with a few Ziploc bags and a bike pump.
Whether you're protecting your gadgets, making healthy posicles, or cooking a perfect steak sous-vide, you don't need any extra gear to vaccum seal things in your home. MAKE reader cashsale shows us how, using a few household items.
The key is basically wrapping your item in two Ziploc bags instead of one, making it a bit easier to suck all the air out. It probably won't be quite as tight as more commercial options, but it should get you by in most situations. Hit the link for more details on how to set it up.
Poor Man's Vacuum Bagging System for Sous-Vide Recipes [MAKE Forums via MAKE]