sharing outlook calendars without Exchange Server

[portia]

Hi,

How would you share your outlook calendar in a small office (10-15 workstations) without the need for Exchange Server. The company doesn't have money to invest in servers. For their needs, sharing calendars will suffice. They don't use hotmail (they use their domain email hosted by a 3rd party company). They use Office 2007.

Quick google showed that there are some plugins but I've seen so many of them that I'm not sure which ones are worth anything.



Thanks in advance for your input.

regards
portia.