Cardmaker is a tool for using CSV files to easily generate cards for your games.
Lately, I’ve taken to making cards for units in my games, rather than putting it on on sheets of paper. Having the cards cuts down on table clutter and makes it easier for players to find exactly which unit info they need.
Epic Slant Press has an article on the lessons they learned from their Kickstarter game. I found it to be interesting for the insight into the game industry.
If you’re designing your own games, here’s a page with some pdf, ai and psd templates for playing cards of various sizes. I’ve taken to making unit cards rather than roster sheets for players to keep track of information in my games.
Gnome Stew has an interesting article on the probabilities of various polyhedral dice.
I don’t know of a miniatures wargamer who hasn’t tried to write his own set of rules. And unless your rules are extraordinarly simple, that means thinking about dice probabilities. Here’s an article on die probabilities with d6s, with a special focus on DBA and Warmaster.