I just put the final touches on taking older machines and making them into Chrome only browser boxes, the GozBrowserBox
You can run it stand alone (I have it on some old 512MB Thinkpads) or in a client/server configuration (I have iBooks and eMacs using this running Chrome with Flash and sound). All it does is boot into a full screen Chrome session, so it depends on what you want to do on how useful it is.
In our public school system this has allowed us to repurpose any machine that comes our way. The limiting factor now is space.
(BTW, there are several security issues with it since the private key for the user browser is publically available in the Github project. It also downloads the configuration from Github everytime the machine is started, which means you have to trust me... Or fork the project and trust yourself!)