Exchange POP3 Connector

I am running Exchange 2000 with 35 users. I use the POP3 connector to retrieve mail from a shared mailbox at our ISP and download into Exchange for distribution to users. The shortest interval for checking mail is 15 minutes. Some users need more imediate access to mail from outside the office. Is there a better alternative to the POP3 connector? Can I create separate mailboxes at the ISP and configure Outlook on each desktop to retrieve mail while staying in the Exchange environment?