Electric Quilt software, a product I can't recommend highly enough. Recently, I have realized that this software can be used for some of my knitting projects as well.
I'm working on a baby blanket for Dorothy, using the " Baby Blocks" pattern by Ann Norling — a lovely, simple pattern. Too simple for me — which is no criticism of the pattern as written, just a recognition of my own preferences.
So, I "drew" up the pattern in EQ and started playing, representing the stockinette in one color and the reverse stockinette in another. This is the variation I came up with: a second internal border of the smaller checks, and a central diamond. My new pattern is still pretty simple, but it will be enough more challenging to keep me happy as I knit it.
And for that matter, it would make a lovely simple quilt, too!