I have tried, but usually don't have the time to do it up so that it looks cute. I did buy a bunch of small tupperware containers from the Korean market to use in lunches, and that's been really successful, but I separate each item so that they don't mush together. When I tried to put an assortment of foods in a larger flat container, they were mushed together by lunch, even if I tried to separate them, which my girls didn't like. There are techniques for keeping things separate, but I just use the small containers, which also greatly cuts down on plastic bag and wrap use.
One recipe I have learned from reading about bento is "onigiri" or rice balls. Those are fantastic for lunches or picnics. Here is a good description on how to make them:
You don't have to wrap them in nori if you don't like it. I usually make ham/mayo filling (not too much mayo, or they fall apart) and ones with "sprinkles" - Japanese seasonings I got at the Korean market.
There are a couple of blogs out there that I can't think of specifically at the moment that also do bento with only Western foods or a mix of international foods. Really it is a healthy way to make lunch if you follow the Japanese proportions: http://www.howtodothings.com/food-drink/how-to-make-bento and http://justbento.com/handbook/downloads/weekly-bento-planner