coming from a boxers backround I feel one of the most effective and overlooked striking skill is a good stinging jab. I havent been in aikido long enough to have used it in a real fight, but I have been in a few in my life, from that and from plenty of sparing style roughhouse with my friends I have found nothing better for maintaining ma-ai than the jab. Especially when your short on room. I also think that it is something all aikidoka need to learn to defend against. It can be wicked quick because of the whip-like action and it offers very little in the way ki to work with, in other words it doesnt commit much body weight.