Former Peruvian President Alejandro Toledo is talking openly about about running again in 2011. Next door in Chile, Eduardo Frei is doing the same. Lucio Gutiérrez just tried and failed in Ecuador.
This reminds me of a great quote I recently read by Martín Tanaka, a professor at the Pontificia Universidad Católica in Peru (who also blogs). He was referring to Venezuela, which under the 1961 constitution allowed a re-election bid after 10 years, but the idea has general applicability:
[The constitution] created the figure of the great caudillo waiting for the chance to make a comeback. Thus, former leaders do not disappear, but grow weak and then reappear.