Marcin Wichary wonderfully writes about discovering an obscure technique for sharpening and de-moiréing old images using FFT or Fast Fourier Transform.

I also loved this bit:

I’ve always had this theory that any long-term project requires two ingredients: things you’re good at, and things you want to learn. The first group gives you a feeling of accomplishment and mastery. The other one? It keeps things interesting.

via Pixel Envy