NOOOOOOO! The alarm didn't go off. You haven't finished packing, and still need to drop off the keys with the dog-sitter, get to the airport, find parking...GAAAAAAAH!
This is a likely scenario on Travel Day, so try to prepare as much as possible beforehand:
1) Plot your travel ensemble in advance: slip-on, flat shoes for quick security-line (no buckles, laces, zippers, etc) and airport sprinting, stretch denim jeans for comfort, tank top, cardigan sweater, and easy jacket (again no complicated buckles or difficult buttons). We'd recommend velcro-everything if it wasn't so unattractive.
2) Print your boarding pass the night before. This way you will not have to wait in the winding line in front of the counter, and if you have no checked luggage, you can go straight to your gate. RUN FORREST, RUN!
3) Get cash the night before: airport machines are occasionally "out of funds", or have enormously long lines.
4) Accessorize afterward: Put your watch, belt, and clanky earrings in a side pocket of your purse until after you get through security - this will save you a few seconds, and when you're late, every second counts. You can actually pull these things off and tuck them in your purse while in line.
5) Keep your ID and boarding pass handy: in a pocket, rather tucked into your wallet or daily planner. You'll need to show it to security, and again, seconds count.
6) Exercise savvy line tactics: Pick the security line with solo business travelers, with small bags. Avoid getting stuck behind families, who will struggle a bit more getting everything together and on the conveyor belt, and might inadvertently put their newborn through the scanner.
7) 3 oz On Top: Throw the 3 oz Ziploc baggie into your purse, on top, so you can just pull it out and plop it in the small tray. Once you get through security, you can pack it properly into your carry-on bag.
8) Go directly to gate: After making it through security, hopefully with your dignity intact, go directly to your gate. Do not pass GO, do not collect $200 (unless it's just laying on the floor in front of you), do not stop at any of the shops you see en route. It is crucial to find your gate first, as it may be much further away that you think. You do not want to be sipping on your Starbucks triple espresso, perusing the airport map, when you discover you need to take a tram past 3 other terminals, then walk 4 miles to get to your gate.
9) Use the moving walkways. The "standers" should be standing to the right side, so you can keep your brisk pace on the left side, and get a little extra distance thanks to the walkway.
And if all else fails
10) Run Forrest. Run.