I'm being offered a 700 MHz tower pc. This would be an upgrade from my old 350 MHz laptop that run Slack and always needs to be plugged in. My old laptop has a nice Orinoco PCMCIA wireless card (that's nice) but is slow because of the CPU. The tower would be an upgrade as far as the CPU but doesn't have a wireless card.

Since I already have a wireless card on my laptop, would it be possible for my laptop and desktop to be wired together so that my desktop could use my laptop's network card without a router in between? I'd be running Slack 10.2 on both pcs.

yeah sure, just enable ip forwarding and masquarading on the laptop and create a dedicated subnet on the two machines. this will make all internet connections esablished by the internal node be snatted by the laptop and then off they go.

I think that part of the question is that you want to connect the desktop and laptop directly without a router's switch tying them together. You can use a crossover cable to connect the hosts.

oh yeah a crossover or a straight cable and a pair of scissors, and you'll be fine. should ideally have a switch or hub and two straights though.

if I run a cable between my laptop and desktop, can I surf the net with at 700 MHz using my desktop?

Yes

But it seems like it would just be easier to get a PCMCIA to PCI adapter, and use the Orinoco card in the desktop machine when you wanted to get online with it.

surf the web at 700mhz?? sounds like a very dubious marketing slogan.

personally sounds easiest to just buy a pci wirelss card anyway....