There's a new trick in wireless networking. Called MIMO, or 802.11n, this new technology has up to 10 times the range, and several times the speed of the older 802.11g wireless networking products, and yet it still works with the older stuff, so you don't have to upgrade all at once.
Computers & networking
To go with your WPN111 Wireless USB Adapter, you will want a MIMO (802.11n) access point.
You don't need it, you can still use your old 802.11 access point, but the Netgear RangeMax 240 will increase the range considerably, and boost the speed from 54 megabits per second to 108 megabits per second. The access point can actually do 240 mbps -- it is the USB adapter on the laptop that limits you to 108 mbps.
However, if you are simply connecting two computers in a home or office, and you don't want to string wires all over the place, the RangeMax 240 can be configured as a bridge, and a pair of them will talk to one another at 240 mbps, over twice the speed of the 100 mbps wired equipment most people install.
I have one of these in our treehouse. With the USB adapter on the laptop computer, I can reach the treehouse from anywhere on our 20 acre farm, and from two neighbor's yards. And if I am close to the tree, I get over 100 megabits per second transferring files from the server in my office.
Netgear RangeMax 240.