I'm breaking my promise to do nothing but actual work until I get this stuff done, but this will be quick:
It would be nice if I had a decent programming background. I'm doing some fairly uninteresting calculations, but they're iterative and it turns out the space for the iterations is very small and the length of "time" that it takes for stuff to happen is very large. This would take about 4 lines of code to write, but I'm auto-filling in excel instead. Did I mention it's a LOT of iterations?
I started to get worried when my excel files broke the 15 Mb mark. Lucky for me, I discovered that if I convert those files from "old excel" to windows 2007 excel, I halve the file size! Who knew? I also haven't run out of rows yet. At some point, though, I'm going to need to make file #2 to fit the iterations.
I'm so glad I'm working in the computer age - this is a relatively insignificant calculation that's taking a silly amount of computing effort.