Are the CyberTV/NT150 Endeavor Set-top Boxes Hackable?

cr0sh asks: "I recently bid and won (on Ebay) a set-top box that I am planning to hack. It is distributed by Liberate Technologies, Inc. (formerly Network Computer, Inc.), and appears (based on a Web search on Google) to be made by Acer (called the CyberTV). Liberate Technologies calls it the NT150 Endeavor System. I have found one other distributor - DEI - on whose page some specs were given. 133 MHz X5 processor (what is this? I am guessing an AMD 586/133), 8 MB RAM, 4MB Flash, lots of ports. The device I received appears to have the ethernet adapter, and not the 56K modem. I didn't receive any documentation or such. From what I have been able to find, the device apparently uses special signals embedded in the VBI of a broadcast signal to bring up Web pages from a Web site, and overlay them onto the broadcast signal, so that you can get an 'enhanced' TV experience. This is accomplished by software Liberate calls TV Navigator. I haven't found any info on the OS used, but I think it may be QNX. Liberate provides a site for development. I was told by the seller that supposedly you can hook up a hard drive and/or a floppy internally, based on information a tech at Liberate told him. I haven't had a chance to open the machine up to verify/find the headers to do such, so I don't know if they are intact or if there would be some soldering involved. Does anyone know anything more about this box, and how 'hackable' it is?"