What am I?

Another what am I blip today.

Got up early for a conference call with the Australians only to discover they had cancelled it during our night. After work we had a long and busy parish council meeting.

Over the weekend I was trying to get a small Viglen MPC computer work with the latest version of Debian to put it into the living room as a music player hooked up to my amp and speaker. After the council meeting I gave up on the Viglen and started to work on a larger but more powerful Compaq I had lying around unused. It's visually more intrusive but upgraded okay without a problem.

Anyhow onto today's puzzle. Hints, it's not a screw and while it's a sort of nail it's not a simple nail but something special. I've had it in my pocket for weeks so it as convenient to blip. What is it specifically?