Wireless Ethernet

I'd like to send data to/from my arduino wirelessly using an ethernet shield.
So far, I have looked at the lantronix wiport at WiPort Embedded 802.11b/g Wireless Ethernet Bridge | Lantronix
and a few devices like this linksys gaming adapter http://www.pacificgeek.com/product.asp?c=212&s=1059&ID=44200&P=F
Any hardware suggestions?

There is a section "WIFI" on the Playground, Arduino Playground - InterfacingWithHardware.

Personally I don't like the price of most WIFI -cards/-shields for the Arduino and hope to hack an old WIFI-router one day. Lots of those have serial-ports on PCB and run Linux. With some open source
firmware like DD-wrt or OPEN-wrt, it may be possible to give arduino wifi capabilities for just a few bucks.