I use one often when cutting in situ laminate flooring. It's so easy to dial in the exact depth so not cut into underfloor.
Great for grooving to inlay banding into timber.
Taking up glued laminate flooring too, just run it through boards and take out complete sections at an easy manageable sizes. Some versions handle 18mm cut depth, but mine only 12mm
The ceramic cutting discs are great for sizing small bits off tiles, and for cutting recesses etc in times to.
Also for cutting channel in plaster and plaster board, just screws a batten to the board as a straight edge and run the Xacto saw against it, and makes light work if of it, repeat for next parallel cut, and tap out plaster, voila, an instant and straight channel for pipework, cables etc.
Great for cutting pipes, especially small copper, and all types of plastics too.
Don't use mine too often, but glad to own one for those type of jobs above.