One. Be smart and check the tv/internet before leaving home. Otherwise you may not be aware that the TTC is on strike and you have no way of getting to work other than walking. For some people, that is a damn far walk. For others (I'm looking at you Schaus) it's the opportunity to sit back and laugh at all the other poor bastards.
Two. Never assume. I know we all know the rule. ass-u-me. But seriously guys. If a new guy starts at your office who just finished his MBA and has 4 years experience, don't assume that it means he'll be able to do a simple project well. Because it could screw your whole week. Believe me.