Many decades ago I used to enter altered states with dxm and an app called flasher.exe would let u pick from different saves to use and it would flash the light on my old Toshiba dos laptop. Used to pop in cds and go for trips in the dark; very memorable.

I use to use Flasher too! It's on the Internet Archive:

https://archive.org/details/msdos_FLASHER_1.51