While N-series routers have largely replaced G- series routers, if you have older equipment, a G-series router is a better choice. The newer and faster N-routers may not be compatible with old equipment, and you won't get the best speeds available unless you upgrade your computer and other network devices.
In the G-series router realm, the venerable Cisco Linksys WRT54G-series router is revered by owners at Amazon.com and Newegg.com, where hundreds of reviews describe it as "stable" and "solid." The series has been on the market for years, and users say the latest version, the WRT54GL (*Est. $45), works fine right out of the box. It includes a four-port Fast Ethernet switch and up-to-date encryption and firewall protection.
But owners really love it because it's the "most hackable of routers," as Eric Griffith of PCMag.com puts it. Unlike most routers, the Linksys WRT54GL is based on Linux -- so Linksys had to open-source the model's firmware by law. As soon as developers got their hands on the code, they came up with all kinds of replacement firmware that you can download to make the WRT54GL perform better and do extra things, including advanced QoS (quality of service), access restrictions, bandwidth usage monitoring and more.
When shopping for this router, be sure the model name has an L at the end. Linksys also made a non-hackable version, the WRT54G, which you'll still find on some store shelves, even though Linksys has discontinued production.