Although Google+ was launched more than a month ago, many applications and services have been already built on it. Which is really amazing considering the fact that, Google+ still don't have a public API. So, I started the roundup with API hacks to understand how other apps might have been made of.
1. PlusFeed
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The idea behind that app started by inspecting AJAX calls on Google+ page itself, which showed that Google uses this URL "https://plus.google.com/_/stream/getactivities/118211149935481259253/?sp=[1,2,"118211149935481259253",null,null,null,null,"social.google.com",[]]" to load your posts, which returns a malformed JSON array of my Google+ posts.
While you cann't use that malformed JSON in Javascript directly, you can use Google Feeds API to convert ATOM feed from PlusFeed into a regular JSON array that you can use.
A WordPress Plugin was already built based on PlusFeed. Also, The same idea was implemented in a PHP class by Rich Kreider.
2. JavaPlus
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3. Google+ Search
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4. Google Plus Search
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5. Google+ Counter
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6. Google Takeout
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7. Google+ Social Statistics
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8. Where to hangout at Google+
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9. Group.as
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10. Share This Circle
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11. Find People on G+
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12. gplus.to
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A similar service can be found at plus.ly.
It is also interesting to note that the old public profile URLs like this "http://profiles.google.com/mikedotmore" now redirect to Google+ profile.
* If you still need an invite to Google+, send me email on Mike[at]MoreTechTips.net from your gmail account that you wish to use in Google+.
* Got a good application or free resource and would like to see it featured on next roundup, send it to me on News[at]MoreTechTips.net , you can also connect with me on Google+.
Thanks for sharing the Resources
Very broad and rich list, thanks
Useful tools, +1 for Group.as and Google Takeout.
Does not work anymore with : https://plus.google.com/_/stream/getactivities/106054122073793220041/?sp=[1,2,"xxxxxxxxxxxxxxxxxxx",null,null,100,null,"social.google.com",[]]