I also keep a back-up MT (a Leatherman Wave) in my vehicle. But I also keep a Mora Companion, BRKT Bravo-1, Becker BK-7, a CS collapsible shovel, a large bow saw (w/ extra blades), and a small hand saw (w/ WD40). In winter, I add two mountaineering style collapsible/extendable snow shovels.
And I have used every one of the items in various unexpected situations, including both snow shovels (remember, I'm in Michigan!) and both saws - most recently, when a fallen tree blocked the only forest service road in or out of Pictured Rocks State Park on a holiday weekend a couple summers ago. The saws (and the WD40 - gotta keep 'em lubed!) saved the day that day!