H&Y Filters announces Revoring Black Mist filter that fits almost any lens without step-up rings: Digital Photography Review
What are 'mist filters' and what do they do to your photographs?: Digital Photography Review
UV filters - do you need them or not? - Nikon Rumors
Amazon.com : B + W 52mm UV Protection Filter (010) for Camera Lens - Xtra Slim Mount (XS-PRO), MRC Nano, 16 Layers Multi-Resistant and Nano Coating, Photography Filter, 52 mm, Clear Protector :
Hasselblad 50156 63 63mm Drop In UV / Haze Filter 1x -0 HZ -Clean in C
Hasselblad Bayonet 50 Haze Filter at KEH Camera
B+W PRO UV-Haze 72mm Filter
How to Use a UV or haze filter for SLR cameras « Photography :: WonderHowTo
Hazed and Confused? Comparing Atmospheric vs Camera Filter Haze Effects