Another use for a phone??

I'm working on a voip PABX project, at the moment using TrixBox, and I have some Grandstream Budgetone 200 VOIP phones. It occured to me that these are little cheap powerhouses waitng to be tapped. The CPU is ?? but it does have a TI DSP chip and at least 256K of ram, 2 10/100M ethernet ports and a crude LCD, 1 LED and 16+buttons, 5V / 1 Amp PS. I don't have the time to start on another project and I need the phones so I don't want to start hacking into them, it just looked like a lot of tech going begging. I'm using the phones because they are the cheapest I could find so they might suit a Uni project??