Yay! I found a wireless adapter that the Raspberry Pi is able to power without an external hub. It’s a Belkin N150 Micro Wireless USB Adapter. Not sure of the range, but it works well enough, and is cheap.
Just to show you how hard-core I am, that’s a screenshot of a browser (showing a picture of the Raspberry Pi + LSTech Solar charger) running on that Raspberry Pi with an X session tunnelled to the laptop you can see in the background. My head hurts now.
Good writeup. For the benefit of other readers, it’s hit-or-miss as to what USB wifi devices use what amounts of power.
I run the “DX special” Leguang LG-N18 USB adapter on my Pi, without using a USB powered hub. No problems. I should note that I am not using a USB keyboard or mouse at all, so I benefit from lower power use.
(To configure the Pi without keyboard/mouse, I use Occidentalis aka the Adafruit Raspbian, and I configure it via SSH using wired Ethernet. Then restart and swap out wired Ethernet).
Also helpful with power management: Get the thickest (in AWG) USB wires you can means less voltage drop across the cable. As does shorter USB cables. And if you’ve done all that, try another USB power supply (try more than two!). I’ve measured 4.8 volts out of a 5.0v USB power supply. For that reason I bought an Adafruit 5.25 USB power supply (which is guaranteed to be 5.25v, even under load).