Nice idea and good implementation. It takes the complete opposite tack from task-focused references. Those may be more useful if you're starting out, but variety is good, and this gives you fast browsing and random discovery, as well as a way to refresh your memory on a particular key or check for binding conflicts. So intermediate-to-expert users could use it to fill in gaps.<p>It also had a potential advantage (not fully realized yet) over a static cheat sheet, in that it has more room for description. It doesn't have to fit almost everything onto a picture of a keyboard.<p>The one negative so far is that several key bindings are missing. g, q, v, V, and ^X jumped out at me.