Kotama Bouabane's Melting Words project is a (great, if depressing) photo series of icy letterforms that spell out relationship-ending retorts. The frozen medium adds mood that any other material would fall short of. Snowmen as a symbol of our fleeting existence – that sort of thing.
Ice once had its own age, so it isn't surprising that other transient, melting works have been created on a larger scale in the past. But a quick search turns up no works of giant, icy words melting in the spring thaw.
Update: A little more searching turned up these sculptures, with another event happening next week.
via shape + colour