So in two roleplays that I'm in, one of my OCs has a Sonic Screwdriver. Though there are many designs for this, it looks like the Ninth Doctor's and has the functions of the Twelfth Doctor's. In other words, it's very useful.

However, I feel like I should list the uses.

1) Unlocking Doors.
2) Melting Plastic.
3) Scanning for diseases.
3) Able to make something uncounsious.
4) Reattach things (not natural).
5) Disable/Destroy weapons.
6) Find ghosts.
7) Sink a ship.
8) Repair organic parts.
9) Disarm someone.
This does take a bit of time, however, as the Sonic uses sound waves to disarm someone.
Please remember, any fighting function on the Sonic Screwdriver is only defensive- it cannot be used to attack offensively. However, the Sonic Gun/Blaster can, where it can either create a massive hole in an object, or be used to attack someone.
10) Remotely controlling the TARDIS
11) Finding the TARDIS's location.