For notebook or desktop tower? Just my own experience: Had a D-Link card, MCPCIA, slipped in the slot on my old COMPAQ Presario 1800T a few years ago, and it was great. I could just 'wardrive' around any neighborhood and town, picking up signals everywhere. I recommend D-Link for this item, based on my own experience(my D-Link router is a whole other story... it still won't hook up my DSL modem, PC, notebook and printer...). Good luck, hope you're pleased with what you end up with.
[hmmm. Me asleep. PCI = desktop.... z z z...   ]

I've been a huge fan of the USB network cards.  Move them wherever you need.

this man speaks the truth

i have the card that you are talking about however, and it works, but it has conflicts with certain sound card drivers, and will cause frequent freezing of the computer. So I don't recommend buying one, it is better to find a USB solution instead (they are usually cheaper anyways)

Gigabyte Makes A Wonderful Wireless USB stick, with 360 degree rotation, and it usually retails for around 30-35 bucks. 802.11g standard, but will work with b.
(not a gigabyte employee, just a customer who bought 3 of them for his little home network)

I'd check out Linsys, and deffinitely any card of repute with Wireless N. Wireless N standards were just agreed on and will become the standard soon. I replaced my wireless NIC and router with an N version and watched my intranet (not internet) connection speed jump from 54Mbps to 270. Makes a world of difference in network server functions and print functions.

N is awesome, but if you're looking into a cheaper setup, then G is the best option. you will need to buy not just a card, but also whole new router in order to support it's full capabilities. Also, an N router will allow for better range than a standard G.