Some potential adventure ideas might include being stranded among humans who don’t speak common, or having to pass for high society folks in a foreign country. In campaigns where knowledge of languages might come into play more often, linguistics could even be salvaged as a way of disguising your accent (in the table for the knowledge skill, there’s even a geography check for identifying a person’s accent). Very campaign specific, and not something I’d implement in every game, but it might be workable in a more intrigue, espionage style campaign.

Speaking of accents, now I’m trying to figure out how an infernal or gnomish accent might sound.