The SnowFlat theme is actually responsive. Here are some samples of exactly the same page and how it adapts to different hardware (screen sizes actually). Of course, you can easily see this by just making the browser window smaller and see how components rearrange based on media queries.
Samsung Galaxy S:
iPad 2:
It might be a bit buggy in some scenarios, particularly in RTL mode, but the bugs shouldn't be too complex to fix.
