The TechZone has posted a review of the TrendNet TEW-637AP Wireless Easy-N-Upgrader.
A quote from the article:
>>> TrendNet TEW-637AP Review
In a nutshell, it's basically just a wireless access point that connects to your existing 802.11b/g router. The connection to your existing router is not wireless; instead, TrendNet provides you with a short Ethernet cable. The idea, I guess, is that you can effectively keep your existing wireless settings on your existing wireless modem, while being able to blanket the same area in a sea of high-speed 802.11n goodness. You upgrade to wireless-N without having to replace your existing router.
>>> TrendNet TEW-637AP Review