Ben Heckendorn get all the attention, fellow modder Brian Gardiner has fired a shot across the bow with his latest creation, the palmPS2. While it's a generation behind Heck's most recent mod, it certainly looks to hold its own in the usability department, with the fit-and-finish to match. Gardiner even went as far to include as many original PS2 parts as he could manage, and kept the size down by opting for an external battery pack. The only downside, apart from being far beyond the skills of most of us, is that the screen apparently suffers from a bit of a green tint due to the PS2's RGB output.
Of course, you could just wait for that PSP download service, but that wouldn't be nearly as satisfying now, would it? Come to think of it, you might just be better off sticking with Heckendorn and his two-year-old take on this same project -- sometimes you just gotta go with what you know.