Anyone know where I can pick up some security/tamperproof bolts (torx or otherwise) that fit seatpost, seatpost rail clamp, etc? Looking for a place I can order them individually and not in bulk. Atomic22 and Pinhead are a tad pricey for my taste.

Not high security, but decent for most situations. Allen and Torx bolts with center security pin.

Security Bolts | Bicycle Bolts

Exactly what I'm looking for BUT I emailed the guy at that site a week ago and he never got back to me. Not even sure if the site is functional. Other options?

[MENTION=172590]rushbikes[/MENTION] did you ever do this? I also want to order from there but don't know if its legit or not.

Ebay?

Great auction site IIRC

Metric? This is 'Merica.

Imperial Security Torx Button Head Screws - AccuScrews




Edit: I love the irony of this being a UK site.

McMaster Carr is the place to go for most anything with bolts - McMaster-Carr.

Bolt depot is also a great place www.boltdepot.com.

Can anyone help a bikeforum buddy out with the measurement details of common screws

From my wonky measuring I can gather that:

Rack/braze screws are M5-0.8 X 12mm
Handlebars are M5-0.8 X 22mm
Seatpost is??

Thanks!

Every bike will be different depending on components used so someone else's measurements are useless for you. What you need to be aware of that has not be mentioned yet is that a lot of bike components use non-standard fasteners, typically with much smaller head diameters than a standard fastener would have. Rack braze-on and water bottle cage bolts have a lot more flexibility as they don't sit in a recessed hole but practically every other bike bolt does and that will limit how compatible off the shelf hardware is.