Sure they exist. Lots of skis out there are suitable for track skiing as well as some backcountry stuff. Of course, there are trade-offs. You won’t find a pair of super-skinny, groomed-trail skis that will float much, or super-wide backcountry skis that will fit into groomed tracks. But you can find some suitable for a variety of terrain.
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Fischer’s BCX E-99 Mountain Crown ski, for instance, is wide enough to offer decent float on ungroomed snow, but narrow enough to fit into the tracks on most groomed routes. Very light, with enough sidecut to make turning easier and metal edges to hold hard snow and ice. Price is $259 (www.fischer-ski.com), but you might well score a better deal if you buy a package. For instance, match them with Rottefella NNN bindings ($60) and Alpina 1550 boots ($159). You probably could get it all for 10 percent less than the combined price.
For fewer bucks, Rossignol’s Evo Action AR skis ($139; www.rossignol.com) will also work well in-trail while offering enough float and rough-terrain performance to wander into the woods. It’s a pretty short ski for maneuverability, and like the Fischers boasts a waxless base. You could put the same bindings/boots with them, or step down a little to a pair of Salomon D7’s ($100; www.salomonski.com), a comfortable boot that can take some light touring while working well on groomed trails.