A blog that I follow on a regular basis is from Aussie ham Peter Marks, VK2TPM. He posts from the perspective of an experienced ham who is really starting to get bitten by the homebrewing bug, so it's a real pleasure to see him discover some of the things which make that aspect of the hobby fun. In his latest post, he introduces us to his DDS-60 controlled by a bank of BCD switches. The whole shebang is tied together with an ATmega32 using C code compiled by the avr-gcc toolchain (my favorite).
I love this for a couple of reasons. First off, it reminds me of the first major homebrewing project that I attempted, the W8DIZ MultiPig. One of my favorite aspects of it was the PLL controlled by BCD switches exactly like this. As a side note, I never did successfully complete the MultiPig. Not for lack of effort (or ability, I think), but because I went and made some stupid life choices. However, I'm happy to say that I was able to cannibalize the remnants of my MultiPig for many successful homebrew projects later on. The second reason is just the cool factor. I guess it's the retro, 70s look and feel of the swtiches, but there's something alluring about the whole tactile experience of using BCD switches. FB job Peter!