Can any atom donate more than 1 lone pair as a coordinate bond to the same metal?
There is a class of compounds, called carbodiphosphoranes, which formally has a divalent carbon&nbsp;(0) central atom. Employed as a ligand it acts as a sigma and pi donor. This capability is also one of the major features to distinguish these compounds and derivatives from carbenes, which are sigma donors and pi acceptors. The following is reproduced from Thi Ai Nhung Nguyen and Gernot Frenking, Chem. Eur. J., 2012, 18, 12733-1748:



Similarly carbodicarbenes (substitute the phosphine with a carbene), also known as bent allenes, are also double donors. 

This post shall only serve as an example, I am quite certain, there are more compound with this kind of bonding motive out there. Nicolau mentioned $\ce{OsO3N^{-}}$ and other metal nitrido complexes, which he will hopefully extend in an answer.