I've had my eye on something along the lines of: http://www.hardkernel.com/main/products/prdt_info.php?g_code...
Quadcore, 2gb of RAM for 65, seems like a nice step up from the Pi.
The Pi is... Sort of mediocre as a desktop (even as a thin client) and too complex for most hardware projects. We ran a number of them as digital signage clients for a while (https://github.com/sapo/digital-signage-client) and eventually moved to Android boxes (https://github.com/sapo/android-signage-client) because even with the recent improvements to WebKit and X the browser simply wasn't up to par.
Worked reasonably nicely with videos, but I keep wondering how much more useful the Pi would have been (for signage, mind you) if they had released their internal Android build.
Edit: forgot to mention I have five Model Bs in a cluster (http://github.com/rcarmo/raspi-cluster) where I run distcc and toy with Java/Clojure/Hazelcast. It's fun, but requires a fair bit of patience.
You can check the load here: http://rcarmo.sl.pt:8888
These things look nice, but I've read some stories about being difficult to get a custom distro to boot (ie. one other than the default distro downloadable on their site.). If the default spin of ubuntu is good enough for you, that's great, but you probably wont get fedora arm booting or anything.
Wandboard is nice -- quad core, 2gb ddr3, 2 mSD slots, SATA, etc. It's a bit more expensive, but from what I've seen creeping the hardware forums, it has better compatibility.
AFAIK none are currently cheaper than the RPi, but they're close and you get a lot more features along with a faster (dual-core, even) CPU.
Anyways -- I'm looking into checking out Wandboard now, as it seems most of the distros that have ARM releases now cover this board natively (no hackery required).
Quad core Cortex-A9, 2GB ddr3, 2 mSD slots, HDMI, SATA port, and all the bells and whistles.