Useful. Though less easy to use on rounded surfaces, where most of my drips happen.

Always remember to let the finish harden properly first before trying any remedial action. A blob of finish will take a lot longer to dry than a thin coat will, so I'd leave it a couple of days (which is why I normally don't bother to fix runs until I've done the last of that particular coat). Try and remove a blob too soon, and the soft finish in the middle can rip out and leave a big pit in the finish instead (which could go through right to the wood).