Or, you could do what our co-loc does, have a large coffee can with screws, nuts, etc and a few shared screwdrivers in another. On your way in, grab the nuts/screws and a screwdriver, on your way out put unused and extras back in the can.
I like this idea better - which is what one of our DCs does for snacks and food. Box of Pop-Tarts, with an honor system can for payment. Partially for the staff, but they put it out in the customer area along with free coffee. Coke machine costs $0.50. There is at least one operator on duty 24/7; if I really needed to I could go knock on the door and have them scrounge up tools and screws. There is a Home Depot a half mile away failing that. This all sounds a little silly compared to the normal datacenter facility issues like power, security, telecomm... but indeed these touches go a long way towards customer satisfaction when you're there for an entire weekend for some big install. Next time we look for new facilities, I know I'll have these in mind. An aside: There is a special place in hell reserved for those who throw out "unneeded" rack hardware. ;) -- Jameel Akari