Palm Operating System
In terms of the Palm OS, there is only one handheld, the Palm Solution Group's new Tungsten C,which integrates W-iFi. Other than that, a couple of Sony CLIE handhelds feature a proprietary CompactFlash slot that is designed to only accept Sony's own CompactFlash W-iFi card. (This has been controversial among Sony CLIE owners who would like to use that slot for other things, such as memory expansion and peripherals. See CLIE CompactFlash Memory Card Support on the Way).
Sony CLIE Handhelds
Sony's PEGA-WL110 Wireless LAN Card ($150) is compatible with the following Sony handhelds:

CLIE PEG-NZ90
The pricey ($800) CLIE NZ90 is the Swiss army knife of PDAs, as it appears to include everything but the kitchen sink. It features Palm OS 5 as well as a ARM-compliant 200 MHz CPU. A built-in 2 Mega-pixel camera, a first for a PDA, supports a 1600x1200 resolution and includes a 2X Digital Zoom, Strobe Flash, Auto Focus, and Manual Exposure Adjustment.

The device also has a thumb keyboard, a removable lithium-ion rechargeable battery, integrated Bluetooth and audio support. It has 16MB of RAM, measures a rather large 3 x 5 5/8 x 29 or 32 inches (depending on whether the device is open or closed), weighs a hefty 10.3 ounces and, of course, includes a Memory Stick slot for memory and the CompactFlash slot for the W-iFi card. The NZ90 also features Sony's nifty and large tablet style display that rotates and has an excellent resolution of 320x480 and 65,000 color support. (Stay tuned, as Palm Boulevard will be reviewing the NZ90 in the coming weeks.)
CLIE PEG-NX70V/NX60
The more compact CLIE NX70V/NX60 and far less pricey, $500 for the NX70V and $400 for the NX60,, feature a similar tablet design to the NZ90 and the same 200 MHz processor. However, the NX70V's digital camera (the NX60 doesn't have one) supports a more modest 310,000 pixels for a resolution of 640x480. Like the NZ90, these handhelds have a display that supports 320x480 resolution and 65,000 colors. It has 16MB of memory, audio support, a thumb keyboard and once again the Memory Stick slot for memory and the CompactFlash slot for the W-iFi card. It measures and weighs a more pocketable, though still not very compact 2.9 x 0.7 x 5.5 inches and 8 ounces.