Ideas for a "wireless repeater"?
 

Hi -

I have a DSL modem with four ports and a built-in wireless router downstairs. It works great: I have wired Ethernet for my PCs downstairs (all plugged in directly to the DSL modem); my son has great wireless access upstairs (using the built-in wireless in his laptop).

PROBLEM:
I want to add another, desktop, PC upstairs. I've been trying to use wireless, with a plug-in a Linksys USB stick. It doesn't work worth crap :(.

I'm considering a) getting another phone jack upstairs, and moving my DSL modem there, or b) stringing some CAT-5 cable from the modem downstairs to the PC upstairs. Putting a wireless PCI card in my upstairs desktop PC might also solve the problem, but the PC only has one PCI slot, and I'd rather keep it free, if at all possible.

QUESTION:
Is there any kind of "wireless repeater", where I can a) get wireless access from my DSL modem/wireless base station downstairs, and b) give me some spare Ethernet ports, so I can plug in desktop PC (so the PC can have a wired Ethernet connection)?

POSSIBLE SOLUTION:
I have an old Linksys WRT54G router that I'm not using.

Q: Is there any way to configure it for this purpose?

Q: Would it be possible to use it for this purpose if I installed OpenWRT?

Thanx in advance .. PSM