Harrison Ford is apparently in very early talks to reprise his role of Deckard in the much rumoured sequel to Blade Runner that Ridley Scott has agreed to direct.
According to Twitch Film, Ford's involvement thus far is tenuous at best, but the actor is at least interested in returning to another one of his iconic roles. Scott is of course currently putting the finishing touches to his science fiction epic, Prometheus, which is in the same wheelhouse/universe as the Alien series - but apparently not an official sequel. Although the more we see of that film, the more it feels like more like a direct companion to those productions - and pretty damn spectacular.
When I spoke to Ford for Cowboys and Aliens, he was coy about future projects but mentioned that he was working on a film about an aging Wyatt Earp, helping about a friend in the big city. That film was looking for funding but it's not clear if has bagged it as of yet.