Although interchangeable DSLRs and mirrorless micro 4/3 models the best photos, for amateurs and enthusiasts, a compact point and shoot still rules the backpacks and pockets of travelers (minus camera phones out of the equation, which seems to be eclipsing them all). Although you generally can't switch lenses with permanent single lens model without some serious hacking, you now can a circular polarizer with the simple technology of magnets!
MagFilter by CarrySpeed offers a very simple magnetic add-on filter system for use with compact cameras, making that awesome new Sony RX100 or Canon S100 more flexible and effective when shooting in bright/reflective environments.
Polarizing filters work by cutting the amount of polarized, or reflected light, that reaches the digital sensor. Polarized light can be found everywhere, including reflections on the surface of water, glass, reflecting from the surface of leaves, and even reflect from the soft blue of the sky. Polarized light often makes objects appear shiny. The use of a polarizing filter can reduce this, and will help saturate the colors, particularly in landscapes that contain foliage and a vast blue sky. Polarizers are very important filters and will retain information during image capture that is normally lost and cannot be recovered in post processing.
The $24.99 36mm Polarizer MagFilter model fits the Canon Powershot S95/S100, while the 42mm Polarizer Magfilter (currently sold out) fits the Sony HX9V, Sony HX20V, Sony HX30V, and Sony RX100.