A lepton (λεπτο) is also 0.01€ in Greece. See: Greek euro coins.
A lepton (Greek for "light", as opposed to hadrons which are "heavy") is a subatomic particle that is not made of quarks. The leptons are the electron, the muon, the tau, and their respective neutrinos.
All known leptons have a negative or neutral charge. There are 6 types of lepton, 3 of which are negative, the other 3 neutral.