Using a UPS as a transformer

So, as part of the Munich prep, I've been wondering how I can deal with my various American devices. We've been encouraged to leave behind our glorious TV (which I'm not sure I agree with, but then again our current unit is getting a little long in the tooth), but of course I will still have our wifi router, my Wii, and chargers for various devices.
Everyone seems to say that you need a step-down transformer in order to deal with the 220v power in Germany, but I've been wondering why I can't just use a UPS that can take 220v in and put 110v out. Theoretically, a UPS has two inverters - one leading into the battery and another leading out, so in theory (from my extremely limited knowledge of electronics) I should be able to use this in place of a transformer, with the side benefit of getting power redundancy and conditioning. So, I hit Google just to confirm, and I haven't been able to find one single account of anybody doing this. So now I have to face the choice of spending (and possible throwing away) $150-$200 on a decent dual-voltage UPS, or just dealing with it over there (which will undoubtedly cost more). But what really weirds me out is my inability to find a single account or testimonial of this on Google.