How do other people keep code current accross multiple machines? (something other than DropBox) [duplicate]

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• What are your favorite version control systems? [closed] 15 answers

I am a hardware/infrastructure guy going back to school to get my degree (FINALLY...) and am taking some low level intro programming classes. On top of the JAVA I am working on at school, I am also tinkering around in some other languages. I work in a shop with some very talented developers and am attempting to learn as much as I can from them. Basically, learning a bunch on my own to write code that will make my infrastructure job easier, so I have more time to learn.

With that said, I spend 90% of my time using eclipse, and 8% in BlueJay (blah, I know) and 2% in VS Express. Because I have 5 different machines between work and home, I am having a big issues keeping my code for various projects up to date when working on different machines.

I tried using Dropbox, and setting the local folder on all my machines to my workspace in Eclipse, and that worked great for a week. Then I found out that the company was getting on users for Internet Usage, because their Dropbox was keeping a live connection to the web 100% of the time that it was running. I have tried the old school thumb drive approach, and I keep forgetting to save most recent to the thumb drive.

So, basically, what I am looking for is advice on how users keep their code up to date? Are there any similar utilities like DropBox, and only attempt to sync when stuff is changed? Are their any other suggestions for an online repository that I can do this with, without logging 50+ hours a week of time on our Firewall report?