The book, though, is more a labor of love than a cash cow.

Europe has not been just a cash cow, but an important source for political thinking.

A long time ago, so I guess it makes sense for them to go back to their original cash cows.

The hope is that stars become the next cash cows.

"In my opinion, they don't want to make this information available, because these people are cash cows."

"Local phone service is the big cash cow," he said.

Too often, she feels, public service is seen as a cash cow instead of a calling.

Yet the rich are still getting the last bit of milk from their cash cows.

"Over the years the cash cow was the race track," he said.

But the core, first year books that are my cash cows don't really ever change.

And who knows if any of those hit pay dirt?

But now, sitting with his feet up on the coffee table, Sean hit pay dirt.

For the record, I agree, we just hit pay dirt.

Sometimes it takes a couple of tries to really hit pay dirt.

I spent two years going through the files, looking for pay dirt.

Even if you hit pay dirt, it will probably be a modest amount.

So far I hadn't hit pay dirt, but it was fun anyway.

Once in a while you might hit pay dirt, but the process is tedious.

It was the kind of pay dirt I didn't want and wasn't looking for.

I could tell from Johnson's voice that in this case, the strategy had hit pay dirt.