Deadly Computer Blog has some plans for a DIY Server Rack, who says you can’t buy computer gear at Lowe’s and Home Depot…

“So, this is something mike has been looking to make for the past few days, ever since he got his new computer case for his awesome new computer. He originally wanted to buy a server rack, so he can mount his case in it, and mount the NAS he has with it, but those cost lots of lots of money. So, our solution, after thinking up at night, was to make one ourselves. I suggested iron gas piping, and mike suggested angle iron. Mike won because in the end, it would be easier to build with angle iron.”

This project uses a Dallas iButton to operate an electronic lock. Have a look at the full article for lots of detail and project source code to build your own.
"This electronic lock can be used with any type of iButtons you may already have, since the only thing needed is the internal serial number, that’s different for every iButton. The command used to read the serial number is the same for all iButtons. The iButton family code that goes with every iButton, can be anything and is calculated as part of the whole serial number. We must also notice that DS1990A series iButtons are the cheapest. This electronic lock designed to work stand-alone and it’s easy to construct. What the user sees (outside of the door for example) is a iButton socket and a led. From inside the door, we can open it using a simple push button. For the actual lock of the door a solenoid and a bold are used. Solenoid must be rated at 12Vdc. iButtons serial numbers stored in memory can be removed and updated when needed. One master key is used to manage the rest of them. Totally a number of 9 different keys can be stored in memory."

(more…)