The Benchmark Email Java SDK by Benchmark is available for download on the page provided. It allows to communicate with the API to implement email campaigns, events, and marketing features into applications. Developers can work with most of the API methods available on the documentation.
With all of the new APIs opening-up these days and increasing emphasis on development in the cloud, it's timely that next week is Mashup Camp. Now in its eighth run, it is free and once again there will be lots going on. Over at InformationWeek, co-founder David Berlind gives a good summary of the event. And although over 350 people have signed-up there are still a few spots available.
PowerInbox’s original attempt to save e-mail required that users install PowerInbox alongside their email client. Although users enjoyed the app functionality within their inbox, the bothersome step of installing PowerInbox limited adoption. PowerInbox has removed the install step with the launch of its open API: Connect API.