This is a big topic, but generally, yes. You can use an Access front-end application with a remote database in several scenarios:
Access - SQL Server (see my "Best of Both Worlds" presentation at
http://ow.ly/M2WI)
Access - Azure (
http://www.fmsinc.com/microsoftaccess/cloud/link-to-azure-sql-database.html)
Access - Access using Terminal Services
Access - SharePoint (needs 2010 for optimal setup)
Note that you really can't do remote applications using a normal Access back-end. It just isn't optimized for this.
Cheers,
Armen