[AndyCalling]

Or...

You could get a Shub and run it in 300meg mode at 5Ghz for your laptops with dongles (running on a 40Mhz channel at 2.4Ghz, ie. for 300meg mode, is poor form with neighbours sharing the spectrum). Then connect your old router to it as a wireless access point to connect all your old 2.4Ghz 'G' devices through. You can also 'ninja link' your netbooks/laptops with 2.4Ghz cards in them to the 'G' router when you just need to browse the web, and stick in your 300meg 5Ghz dongle to do the heavy stuff.

With no more cost than the Shub will be costing you anyway, you can have your cake and eat it. Yum!