Aengus's hits sometime between 3-5pm or so and goes until 6-7pm, unless you can trap him with a nap beforehand. Most of the time, Will conquers the Witching Hour with the Moby wrap and a trip outside. Aengus cannot resist the snuggle. I, however, tend to use what my son considers my greatest assets: the breasts--I basically keep him eating until he lulls off to sleep.
Today, I was not so lucky. And, I was foolish enough to try to take him with me to the lab for some research. (Naive, I know.) He was not pleased. I left after I couldn't console him with bouncing, the Moby, or even the breast. The fussiness continued until just before 6, when he finally settled after eating for an hour and a half and I was able to put him next to me on the couch for a nap.