Like any good C++ developers, having interests in a good open-source project and making contributions to it can come a long way to learning C++ the hands-on way. Without further ado, below is a list of quality and exemplary C++ projects, all open-source:
arora
ClamWin
Google Chrome
googlemock
googletest
NetBSD
Notepad++
Qt
Songbird
VideoLAN
Webkit
WinMerge
WTL
wxWidgets