Are you compiling a table of possible events to roll (or equivalent) for? These suggestions are based on that idea, ignore me if they're not what you're looking for. As far as I know these can all either happen with a game mechanism or be extrapolated based on what's available.
Supernatural stuff? Alien abduction. Discover someone unexpected was disguised as an alien. Unexpected vampire attack. Good old fashioned ghost-scare with your own spin on the outcome (in Sims 2 they could kill your sim that way.)
Um. Food poisoning, earthquake (actually possible with the lot trait), satellite strike (imaginary). Learn you're adopted. Fired from job.
Relationship misunderstandings - innocent or not (Sim mistakenly thinks partner is having an affair and reacts accordingly; Sim mistakenly interprets friendship overture as romantic, etc).
Randomly selected wishing well outcome.
Sim loses/gains a huge sum of funds.
Running dry, hehe.