source (singular) claims that Logitech is developing a UMD drive add-on for the PSP Go. The source has neither price nor release information, merely stating that the "only problem is that it'll make the PSP a little bulky." Logitech's UK office told the outlet that it's unaware of such a device and that it "may be something the US office is working on." We've contacted both Sony and Logitech for more concrete information.
Beyond the fact that such an add-on would undermine what the Go represents (not quite the "only" problem, is it?), the likely price of such a device, in addition to the base cost of the PSP Go, would not compare well to the already lower cost of a regular PSP with UMD drive. Now, if the add-on could "install" your old games, that would be something ... Update
: Logitech tells Joystiq: "This is not something that our company is working on."