``A short proof of Jacobi's formula for the number of representations of an integer as a sum of four squares'' (with George Andrews and S.B. Ekhad), (appeared in Amer. Math. Monthly v.100, no. 3 (March 1993), 274-276).

Many (perhaps all) ``deep'' results from the theory of modular functions and elliptic curves (e.g. FLT), are but limiting cases of completely elementary (`high-school algebra') results on q-series, which are shaloshable. This is one example.