Iterating and printing

Ok,
Imagine I have a class

class C
{

};

ostream& operator<<(ostream& o, const C& c) { ...}

I have a collection of these objects, in an STL list or vector and
want to do 2 things:
1/ Print all these objects to cout
2/ Write all these objects to a long string

Now, I wanted to try and use for_each and avoid my usual code of

stringstream s;
for( collection<C>::iterator it = Collection.begin(); it !=
Collection.end(); it++)
{
 cout << *it;
 s << *it;
}
string res = s.str();

So I tried a couple of options:

void printC(ostream& o, const C& c) { o << c;}
for_each( Collection.begin(), Collection.end(),
bind1st( fun_ptr( printC), cout) );

which wouldn't work because of a problem of refs to refs,

so i started on the second problem and created a class

class P
{
public:
    P() { //Setup code }
    stringstream s;
    string getString(){ return s.str();}
     void operator()(const C& c) { s << c; }
};

and tried to pass this:
P p;
for_each( Collection.begin(), Collection.end(), p );

which fails because we can't copy P, because it contains a
stringstream which can't be copied.

So i currently have

class Q
{
string s;
void operator()(const C& c) { stringstream ss; ss << c; s+=
ss.str(); }
};

Q q;
for_each( Collection.begin(), Collection.end(), q );

which, correct me if i'm wrong, seems like a very crude way of doing
it!

This seems like a fairly common task!
Any thoughts on the matter would be greatly appreiciated!

Michael