Realistically there has been a lack of great alternatives for the provision of Business Class Calendaring and Email. However, with the advent of Google apps this may have indeed changed at least for the smaller business.
What you get for £37 per mailbox per month.
- 25Gb of storage
- Access anywhere in the World via Webmail
- Access mail off line with your web client such as Outlook
- Access mail with mobile phone
- Professional email address e.g. user_name@your_domain.co.uk
- Spam filters that really work
- On Line Calendar
- Shared Calendars
- Service Level Agreement (99.9%)
This compares favourably with Hosted Exchange at ~£60 per box per year.
Compared with running an in house Exchange Server meeting a 99.9% SLA the savings are more significant.