Nowadays there are a lot of services, such as email, chat, voice over IP, document sharing, blog edition, etc, that are offered through Internet by diverse companies like Google, Hotmail or Skype. Most of them have become essential (email) and some of them (softphones, file hosting…) will become, either for particular users and small enterprises.
Gmail is a good choice for users and small business which cannot afford their own server. It is the most balanced service, it supports POP3, IMAP and MS Exchange, it is more secure and has advanced filters and labels.
A softphone is a software program to make telephone calls over the Internet. Nowadays, there are a lot of companies that provide voice over IP: AOL IM, Bink, Bria, Brosix, Jitsi, Oovoo, Skype and Yahoo Messenger.
For a particular users the best option is Skype. It offers text messaging, voice calls, video calls and conference calls for free in a security way.
For small enterprise the best option is Brosix because it provides private Instant Messaging (IM) network and control, has a powerful collaborating tools, doesn’t need a maintenance and has strong security. It is an alternative for those who are more interested in business features and less in personal communication.
Amazon S3 offers very large storage which can be useful for large companies. It is the only one which offers redundancy and advanced security options. However, Dropbox would be the most balanced service for users or small businesses while Amazon S3 suites the need of massive storage for larger companies.
Suites of services
Google provides diverse services for personal communication and professional business with good compatibility with existing user software. It has more services than Microsoft and is continuously developing more. Because of that, either for particular users and for small enterprise Google services are the best.