You've come across them all already. One is the dagger symbol which either acts like an asterisk to draw attention to a footnote or means that the person with the obelus next to to his name has, sadly, snuffed it.
It looks like this:
The other sort of obelus you know as well, because it looks either like this:
which usually means divided by (although some Scandinavians used it to mean subtracted by until fairly recently, and in Italy it sometimes indicates a range of values) but can also be used to mark a passage of a book that's reckoned not to be authentic. This kind of obelus can also look like this:
The plural of obelus can be either obeluses or the delightful obeli, so this means that if an extremely ancient and frail scholar has been marking up a book for suspect passages there's always a chance that he or she will do it using wobbly obeli.
One can but hope, anyway.
Word To Use Today: obelus. This word comes from the Greek obelos, which means sharpened stick, spit or pointed pillar. It's basically the same word as obelisk.