News of the availability of very low cost AD9850 DDS boards from China via eBay has swept the home brew radio community in recent weeks. These chips alone were quite expensive and the surface mount soldering was a challenge.
Now the chip, mounted on a nice carrier board, with 125MHz crystal, is available for a very reasonable price. Here's mine sweeping a few frequencies near 10MHz:
The Arduino code I used is from NR80 which in turn is based on code from Andrew Smallbone.
I simply powered mine from the 5V on the Arduino and it seems to work just fine.
Our plan is to make a little crystal replacement board for QRP purposes with a multi-position switch to select the frequency.
Purchased a blank Arduino shield board and have now mounted the DDS board nicely for future software development.