We had a power cut this afternoon. I was attending a seminar on analysing the results of Combinatorial Chemistry experiments, and the projector went off right at the start of the presentation. The room lights were already off, and the laptop which held the slides was still on, so it wasn't immediately obvious what had happened.

There are roadworks nearby, where a gas main is being replaced. We later found out that they had severed the electric cable, cutting off power to most of the site (which includes the University and various shops and offices).

The seminar had to continue in the old fashioned way, by writing on a board. Only the end boards could be used - the projector screen couldn't be retracted because it was electrically powered. Within minutes of the presentation ending, the power briefly came back on, but it turned out to be a false alarm and everywhere was plunged back into darkness again.