Spam Bots/E-mail Addys

Just curious... If I have a site that stores information about people in a database, including e-mail addresses, and that information is only viewable when called via a user-specific variable, i.e. their alias, can spambots still harvest those e-mail addresses? So for instance I have a page called 'users.php' and to find the e-mail address for John Smith, you'd follow a link that directs you to users.php?alias=johnsmith - I guess my main question is, can spambots follow those types of links, get the resulting page, and harvest the address off that? Is there any way to combat this? Any PHP scripts, classes, functions that can 'hide' e-mail addresses? The site I'll be building needs to have the e-mail addresses available, but I don't want to subject users to more spam than they probably already get. Jason Soza