How Do You Protect the Bottom of Your Bags?

Right now, I keep all my lipglosses and pens in a separate little zippy purses, and I don't carry food or drinks in my bag. I'll have to check out that chameleon, though. It looks like a great solution!
 
Yet another excellent reason to get a chameleon insert! Not to sound like a commercial for them or anything, but the inserts are great at organizing your stuff and they're like purses INSIDE your purse, so they also keep stuff from directly touching the bottom of your bag.
Hmmm... I've never heard of that. Thanks for the suggestion.