A little Chicago ISV called LimitNone is suing Google for nigh on to a billion dollar charging it with misappropriating its trade secrets to beat back Microsoft Office.

Seems a year ago March LimitNone shared its mojo for migrating Outlook users and their calendars and contacts to Gmail with Google and according to LimitNone’s story the widgetry turned up in Google Apps despite Google’s assurances that it had no intention of developing a similar product.

It says Google had trouble building such a thing.

Google reportedly took LimitNone and its gMove product around to customers like P&G, Intel and Morgan Stanley last year and then in December told LimitNone that it would be releasing a competing product called Google Email Uploader that would be free to its premier customers.

The suit claims Google stole gMove’s look, feel and functionality.

The complaint alleges that Google Apps executive Scott McMullan told LimitNone that the potential for 50 million users was “just too big to come from someone else” and that “this is how Google operates.” Those 50 million users are what LimitNone is basing its damage claims on.

LimitNone, which is using Kelley Drye & Warren, a law firm that has sued Google before over AdWords, is now focusing on the iPhone.