how to include() a string

Hi, I'm trying to include an HTML string with PHP tags in it, and get it parsed just as if it were contained in an include()'d text file. For example, let's say I have the string $parse_me = '<p><?php echo $REMOTE_ADDR; ?></p>'. How do I include it in the page (*before* it gets parsed) without doing any I/O (i.e. writing it to a temp file and include()ing that one)? Is it possible in the first place? Regards, Luca