When you're in a computer program day in and day out, it's the little things you find that make all the difference. As I stated a few posts ago, I'm a keyboard shortcut junkie, especially with my editing programs. When I was editing in FCP 7, I could go for hours without ever touching a mouse.
I'm still slowly adjusting to Premiere, so I don't know all the new shortcuts yet, but a few have found their way into my repertoire. Aside from JKL, which don't count as "shortcuts" in my opinion since everyone knows them, I find myself using "Q" and "W" in Premiere all the time.
These keys simply do a ripple edit on the clip the play head is within to either the previous or next edit point. It seems pretty simple, but has proved invaluable as I've edited tons of interview footage lately. They allow me to cut on the fly as I'm listening to footage, and within a pass or two of the footage I have a viewable rough cut just because I was able to cut out the footage while playing the media. It speeds up my editing time tremendously, and I think these will be staying with me as I learn all the new shortcuts in Premiere.
What are your favorite keyboard shortcuts? Are there any apps you can't stand to use until you have at least the basic commands taken care of?