Standard procedure recently has been to exchange it (one day remaining) for a 1 day nonupgradable hopper good at any of the theme parks. Depending on your vacation plans the resulting value could vary from around $110. (an isolated day at Magic Kingdom) to about $12. (finishing a multi day vacation started using another, multi-day, ticket).
For a long time Disney has not bothered restricting old tickets to the parks that existed at the time the tickets were sold but also Disney has not always offered additional privileges or venues (such as an alternative to Disney Quest) for venues that closed up after tickets were sold.
Almost all pre-2005 tickets were non-expiring, the notable exceptions were "length of stay" room package tickets and a few 4 day tickets good for one day at MK, one day at Epcot, one day at Hollywood Studios and one day good at any one of the preceding, all days consecutive (Animal Kingdom wasn't open yet).
Tickets were always non-transferable. For awhile, some multi-day tickets were advertised: "... good for any 4 (or however many) days out of the rest of your life ..."