8gb flash drive with School Days 
That's REALLY useful

Do you live in a FPS IRL?!
fps? no; sadly i live in a dangerous exciting region on planet earth. 
Which is...?

Always with me (I don't go outside without these):
-Cell Phone (Nokia 5310 with 8GB SD)
-Headphones
-Wallet with some cash
-Keys
What I usually carry around (all the above plus):
-ID
-Knife (Victorinox Tourist model)
-Red Sabre pepper spray
-LED flashlight
-Screwdriver (I got it at a computer convention from Corsair, it's small, like a pen and has 4 magnetic tips, the most useful sizes)
-4GB pendrive
-Little mirror, lipstick, perfume and some other makeup I may have
-Alcohol in gel
-Tissues
-Some pens, a pencil
-A4 notebook
-Netbook (sometimes)
-Ethernet cable (sometimes)
-Condoms and lubricant gel (sometimes)
When I go to Uni (all the above plus):
-Another A4 notebook
-More pens, pencils
-Rubber, liquid paper
-Photocopies of the day's subject
-Netbook charger (sometimes)
And there's a day I have to take an A3 folder, with blank paper, the crap I'm working on, several types of pencils, paintbrushes, ink, scissors, rulers, duct tape and more random stuff
