Some excellent posts.
Don't forget about night VFR. One of my scariest nights as a 200h pilot was when the moon disappeared behind a solid overcast and the terrain had no lights (wilds of the unfrozen North). Whirly's description of 'abnormal sensations being normal' was certainly true!
It's hard to know when you're in cloud under these conditions - it is really a form of IMC.
Interestingly, the reported fatalities for pilots continuing into IMC seems to be the same for instrument and non-instrument pilots in the NTSB reports. This may be a reporting error, but bears some thought.
Rgds
CB