Some ideas are as simple as boiling water. I have tried boiling water. It does give you immediate results and satisfaction from watching the weeds wither in front of your eyes, but it is cumbersome.
One blogger wrote that they preferred the boiling water method over vinegar as it does not leave a residue on sidewalks or driveways. You do have to be very careful handling boiling water. I personally don’t think its a good solution if you have a significant area to treat.