One useful thing when managing one's time is to know when a command will complete. I have a habit of using "pv" anywhere I wait for a result so that I know how long it takes:
http://www.ivarch.com/programs/pv.shtml
It's basically "cat", but with a progress bar. Also useful for measuring IO speed and volume (e.g. decompression: `pv -c largefile | gzip | pv -c > /dev/null` )