There are alot out there but the only ones I use macro rune strike to my other attacks so I nevr have to wory about missing the opertunity to use it. It's also very simple. It will increase your dps as well as threat. You can also free up space on your castbar since you don't need the button any more.
To make just make a new macro for each of you major attacks and replace the icon on your action bar. the macro goes as follows.
cast attack name cast !rune strike
The (!) tells the macro to cast it whenever it's actice so it wont try if it's not.
For reasons I don't understand this doesn't work with other rp dumps. Perhaps somone smarter than me can explain why.
"#showtooltip" allows the macro to show the powers actual tool tip instead of the macro code as a tool tip. "/script UIErrorsFrame:Clear()" keeps the red error messages from pooping up after using the macro. Useful to get rid of the error spam any macro may cause.
An Icy Touch -> Plague Strike variation, since you always use the two together: (And one less button on the action bar.)
The "reset=6" ensures the sequence will correct itself if you find you hit the button an odd number of times for whatever reason. I chose six seconds because I sometimes single pull with Icy Touch and need to wait a little bit for things to come within melee range.