Unless Sharp just never offers the SL-6000 for sale (and I believe they already have, in Japan...), I think that the end users will do the rest. The SL-6000 offers the possibility of two-flavour wireless connectivity, with a CF slot for peripheral expansion (GPS, camera, cell phone card, etc) and an SD slot for flash memory expansion limited only by one\'s budget. If it were for sale today (in US), they would be at the absolute head of the PDA hardware line. (Notwithstanding the \"micro-PC\'s\" that resemble giant PDA\'s with giant price tags.)
Witness the die-hard Zaurites willing to pay premium prices for clamshell models (sold only in Japan by Sharp) that have been anglicised by resellers: the quality of Sharp\'s hardware, combined with the flexibility and transparency of Linux, will create its own market, no matter how freakishly Sharp (mis)targets and (under)promotes the Zaurus.
That said, I do think it\'s a shame that what was clearly (and successfully) engineered for the mass market (speaking of my SL-5600 as an example) has been relegated to the geek niche by Sharp\'s failure to promote their product. The average Joe Blow who sinks $400-500 into a Palm Tungsten C could pay less for a SL-5500 (or maybe even 5600) and Wireless LAN CF card, have true multitasking, better stability, more software (albeit without quite the toddlerlike simplicity of Palm SW installation), and never have to face a command prompt--or even install a terminal client, if he didn\'t want to. The SL-5600 is sufficiently \"idiot-proofed\" that casual use (ie anything you can do with a Palm) is far safer than on Palm or PPC.
The \"rub\" is that having a broader user base--which Sharp could have achieved by better promoting its Zaurii--would have meant more commercial (\"plug-and-play\") peripherals, software, cases, and all the other little extras that come to market when their makers think there are enough potential buyers to justify developing them. Sharp\'s marketing failures have not only cost the company revenue--they have also cost the Zaurus and those of us who use it a \"place at the table\" in the handleld accessory aftermarket.