One of the great training sessions I got at Camtronics was Essential .Net from Developmentor.  The instructor and team participated in trying to name all the different ways to do a string in VC++, MFC, ATL, COM, etc..  We came up with 42 I think.  Here are the ones I can remember:

"I'm so sad"

L"I'm so sad"

W"I'm so sad"

OLESTR("I'm so sad")

SysAllocString(L"I'm so sad")

_T("I'm so sad")

_TEXT("I'm so sad")

char *

wchar_t *

BSTR

CAtlString

CAtlStringA

CAtlStringW

CComBSTR

CSimpleStringT

CString

CStringA

CStringT

CStringW

DBTYPE_BSTR

DBTYPE_STR

DBTYPE_WSTR

LPCSTR

LPCTSTR

LPCWSTR

LPOLESTR

LPSTR

LPTSTR

LPWSTR

OLECHAR

System::String

TCHAR

_bstr_t

std::basic_string<char>

std::basic_string<wchar_t>

std::string

std::wstring