Clever, wireless personal organizers. Connected to the Internet over a Radio Cellular Network.
Also, more than likely, is a telephone. 

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Much has changed since Feb02 when the page was created. For example, in late 04 a product called "Globe''''''Trotter Fusion" has capabilities to connect to various WirelessNetwork''''''s, ThirdGeneration (3G), GeneralPacketRadioService (GSM/GPRS), WiFi, etc. Give it another couple years and one can expect affordable BroadbandWirelessAccess addons to emerge. See http://www.wirelessdevnet.com/news/2005/jun/30/news6.html

See a picture of this laptop addon:
http://www.3g.co.uk/PR/Sept2004/GlobetrotterFusion.jpg

In mid 05, the above is already superseded by another product; see http://www.channelregister.co.uk/2005/06/13/sony_ericsson_gc99/.