Around Shanghai, a favorite spot for free wi-fi is the Coffee Bean & Tea Leaf stores.  There's one at Xintiandi, another near People's Square at Fuzhou Lu (near the "CapitaLand" building), and a third near JingAn Temple.  Further afield, out in Hongqiao, another good spot is Moon River Diner in the alley off of Hongmei Lu.  And of course the Coffee Tree is always fantastic. 

There is no great WiFi, but most office towers are full of free and open access points. Come to think of it, most residential buildings are too.

Wish Shanghai had mountains like this

This is not the view from the window of the Coffee Bean and Tea Leaf.