Pavement Weeds
A weed torch (a specially designed propane torch) is a great tool to use on those pesky weeds growing in sidewalk and pavement cracks.
Another option is to pour vinegar or boiling water on weeds growing through pavement, gravel or patio slats. If you're worried about boiling the little critters that live beneath the weeds in your pavement or patio stones, hand weeding with a special 'crack' tool is your next best bet. Check your local gardening store or Lee Valley Tools for options.