Does the system possibly have a game/midi port you could connect an external device to?
Might be handy to know more about the machine in question.
Are you asking about the ThinkPad 386CD? (same as 380ED) The "CD" part means it has a 3.5/CD-ROM combo drive. On the back, it has a PS/2 port for mouse. They all have a parallel port, serial port, and VGA out (so you can add any LPT peripheral, while I think there are some suitable serial-port based joysticks?). They have 16MB RAM internally, then can add one RAM expansion on that. Another nice thing is the CMOS battery is very easy to get to - one panel on back, same compartment as the memory upgrade slot. The battery is right there, don't need to pop open the keyboard. (again, all the parts are interchangeable with the 380ED - at least the battery and memory)
On mine, after replacing the CMOS battery, I found that it still warned about "bad CMOS battery" once (or probably bad CMOS settings) - then after doing a SAVE in the system setup, it never complained about the battery again. Another thing, getting into the setup manually on the 385CD is "odd" - you power on the system, hold F1, power off the system, and keep holding F1 as you power it back on again (and try holding for a minute; I think you have extra memory, it is doing a memory test on that and so getting into the system setup might take longer than usual -- that's just my guess, since I noticed if I take out the added memory, I can get into the system setup more quickly)
EDIT: You *should* be able to add any LPT peripheral (like SDLPT). I'll verify that next weekend, I actually hadn't tried it yet. There was an old 286 that I couldn't get the SDLPT to work on, so it's true, don't take it for granted that it will always work on every system.