Update: On March 20, 2003 it was announced that Cisco had purchased Linksys for a total of $500 million in stock. The purchase, analysts and press releases agreed, was an attempt by Cisco to tap the increasingly lucrative home networking market, a low end which their own products were not able to penetrate. The Linksys brand name was retained, and seems to be making money for Cisco as of June, 2004.
Linksys are also the makers of one of the most popular 'moddable' wireless access points - the WRT54G. This little blue plastic device has become a familiar sight in student and geek apartments, as well as tucked away on walls in small businesses. The reasons for its popularity are threefold: first, its price is quite reasonable (as I write this, it can be had for $69 US with a $10 mail-in rebate). Second, it is feature-laden, serving as an 802.11b/g access point, Cable/DSL router, wireless repeater, wireless-to-wired bridge, or as a member of a mesh network depending on how it is configured. Third, and perhaps most important, its firmware is composed of an embedded linux distro!
In fact, there is a somewhat-thriving cottage industry on adding features to this little box by rolling one's own. The Swedish software firm Sveasoft, in addition to an existing product line, is offering downloads of an entirely custom linux distribution that give the WRT54G and its non-router cousin the WAP54G all manner of cool linux capabilities. These include, but aren't limited to traffic shaping, better DynDNS clients than the stock firmware, shell access to the router and SSH/telnet, iptables-based firewalling, PPTP and/or IPSEC-based VPN endpoint and client services, static DHCP leases with ddns, and much more. Well worth the $20 that Sveasoft charges for a year of updates and support. If you presently use a computer running linux as a firewall, you'd be well served to look into one of these if for no other reason than to lower your electric bill.
This is noded here because it's a common description of a family of devices, all Linksys.