I'm adding this to the Links section.
It's hardly a comprehensive list, but I thought it might be helpful.
I've been concentrating on recent bright novae (particularly the ones
that don't already have variable designations such as RS Ophiuchi) and
supernovae. There haven't been all that many in the past 30 years. I
could go back further.
Novae occur when stars throw off their outer layers and radically
increase in brightness; this may occur again and again with the same
star. Supernovae, which occur when stars literally explode, are
obviously a one-time-only event.
Mark A. Holmes