anton,
If in pristine condition maybe 50-100 dollars if you can find someone that needs a DOS laptop. There are industrial applications that used DOS and a maintainance dept. somewhere might be in need. Most have upgraded software or purchased newer computers with options they need such as RS232 port and a type I, or type II card slot. Also someone who has DOS games or old floppys they want to read could use it.
Good Luck
as a note: anything is worth what someone is willing to pay.