It has happened three times in as many weeks. Between the 4 regular BB's that I frequent-DRN, XDB, ThumperTalk, and Woods Racer as well as two newsletters (CycleNews and Motoworld), Sierra Club is always cookied in my temp internet files now.
What useful purpose would it serve to them to be doing that and how do they get in?
Nope, I've never visited their site-that is what is so wierd. It's like it tags on with one of the off-road sites. I just checked temp files again-it's back!
Obviously, they can't cookie you unless you visit their site, a site they own or a site that the webmaster is up to something. I would doubt seriously that you got it from one of the dirtbike sites you listed? I'd be looking at what other sites I go to.
No cookies for me on Holeshot, TT DRN SBN or katanaplanet.com. Look at the dates accesed or modified and figure it out from there. Wife, kids or friends?
I dunno-it's been deleted off three different times. My wife just hits a few shopping sites (Eddie Bauer, etc) and some baby sites. Mine are all cycle stuff.