I can't give this dev enough praise. This feature has been added as of version 0.50.1
Start the program with "tic80 ." (yes that's tic80 space dot) to use the current directory.
Is there any way to set the folder where tic files are saved on start up? Instead of the default "C:\Users\DePingus\AppData\Roaming\com.nesbox.tic\TIC-80", it would be more convenient (for me at least) to have that folder reside on a USB drive so I can work from different computers. PICO-8 has the -home command line argument that does this. Speaking of which, some more startup command line arguments would be nice too; like -width, -height, -windowed.