I'm on Cox cable, with 4000/512 speed. I'm currently using the original Toshiba PCX2200 that I got from Cox back in 2002. It's spec is 10Base-T, half duplex, for the ethernet connection. I don't use a router.
Circuit City has the Motorola SB5120 on sale for $40 after rebates (no activation required), and I've been thinking about getting one. I understand the Moto would let me do 100 mbps at full duplex, but I wonder at my current speed limits whether I would notice that change.