Another possibility for dice rolls is the off-the-shelf "roll" tag on EN World itself.
Good points: (1) You can't reroll to try again, so it is secure. (2) It's right here, so you don't have to link to anywhere else.
Bad points: (1) It only works from the "Quick Reply" box, not the "Go Advanced" box. (2) You can't edit it: If you try to edit it, any further "Save" you make of that post will simply wipe out your entire roll. (Yes, this means you can't have colored text in your "roll" post.)
In the following, replace "(" with "[" and replace ")" with "]" -- without the double-quote marks of course:
Basic: (roll)XdY+Z(/roll) -- Example: 1d6+2
Named: (roll="Name")XdY+Z(/roll) -- Example: (roll="Attack")1d6+2(/roll)
View: (rollv)XdYbZ(/rollv) -- keeps the "Best" Z of the X dice. Example: 4d6b3 keeps the best 3 of 4d6.
Open: (rollo)XdY+Z(/rollo) -- rerolls and adds any dice that come up maximum. (Exploding dice.)