Yes. This is known as a stacked or parked domain.
If you want domain2.com to go to maindomain.com there is a one time 15.00 setup fee and no monthly fee.
If you want domain2.com to open the files in maindomain.com/domain2/ transparently (i.e.. another site) there is a 5.00 per month fee no setup fee.
Stacked domains do not have a control panel or pop3 email. All email sent to stackeddomain.com will be sent to username@maindomain.com. If you have a professional/reseller account it comes with 50 FTP accounts. You can setup one of the FTP accounts for the stacked domain.
