I just noticed that my reputation score dropped significantly since my last time checking in. Upon further inspection I saw that on a number of older question I asked, someone downvoted my questions, one after the other. Why could this happen? Could it be a system glitch, a moderator review or perhaps even sabotage?
If you check your reputation history for today you'll find the following entry:
+10 Serial downvoting reversed
There is an automatic script that reversed such anomalous vote patterns. Those votes you see were reversed and you regained the reputation you lost from the downvotes.