There's also the options of ad-enhanced accounts. I don't know for certain how many databases you'd get on the ad-enhanced plans though.
There's two options:
Corporate, which requires an banner placed so the user does not need to scroll to see it (near the top of page). This option would give the most extra resources.
Advanced, which is a text link that can be placed anywhere on the page
In both cases the ads need to be placed on every page. The codes for them can be found at:
http://x10hosting.com/panel.php?adcode
To get ad-enhanced you first place the ads properly and then submit a support thread asking to have your account upgraded.