While I posted this one way back in 2012, it bears repeating as I think it is one of the purest congruent conflations out there, and a common one as well. The speaker was talking about her lack of sleep the previous night but that her husband slept soundly, describing him as being out like a log. This is a congruent conflation of “slept like a log” and “out like a light”, both referring to sound sleep. There are a lot of the letter L in both expressions, contributing to the mix up. A big thanks to Donna Calvert for sending this one in. Glad to hear Bill is sleeping well in retirement.