Here is a dataset of emails of a governor in Florida. It contains all email communications this governor made from 1999 to 2007. It contains about 280K emails. It was made public for political reasons I believe.
You'll have to do some Google detective work, but you can find individual .mbox files that have been shared online, perhaps accidentally.
Search google for "filetype:mbox"
Start removing top hits, like "Facebook" and "List, using the '-' (minus) operator: example.
Add a search term for typical ways files are shared, like FTP: example.
Iterate over ...
After some additional search, I found the worked link among of lots, which point to 404 pages.
The worked ones are:
Detailed information about these datasets:
You can download raw emails from the Wikileaks data backup site (wlstorage.net).
Search the file page for 'email'. Clicking on that link will bring you to an HTML email page. But you can find the corresponding email files, and perhaps .mbox formats, with the torrent download - LINK.
Yes there are laws about spam: here's for the US, here are some links about Europe spam laws.
I'm pretty sure that in France (not sure about other countries), unsolicited commercial emails are illegal if sent to a person BUT commercial prospection IS legal so if the email addresses are professional that would be OK.
Anyway, in my opinion the ethic problem ...
The Sunlight Foundation has created websites for two released email datasets (Sarah Palin and Elena Kagan). Unfortunately, both domains are not functioning.
Blog posts: one and two and three.
Luckily, their github repos with code & data still exist!
Sarah Palin - original emails were released on paper and several news organizations have done OCR to ...
You might be able to create an SQL DB by using FERC Enron XERA web application: http://fercenron.omega-caci.com/default.html (user guide).
You'd use the search feature of XERA based on fields, and then export the result to a delimited file, then convert to SQL database for additional queries.
One of the positive things about leaks and data breaches is that they can spawn new corpuses.
Note that since these were obtained illegally, you may not want to use them. Both because IANAL and don't know if there are legal issues and because people could see it as unethical. Some of these can also be politically charged topics, so I'd advise not using many ...
Library of Virginia has archived emails during Tim Kaine's governorship:
Kaine Email Project @ LVA
A Guide To The Governor Timothy M. Kaine Administration Electronic Files, Email, 2002-2010 (Bulk 2006-2009)
Search the Collection
I haven't tried the mail feature, but I think MediaWiki notifies you when somebody else edits the page. There is no reason to send you a mail when you edit the page yourself - you should already know that you have edited it.
If you want to make sure that it works, you can try adding an often edited page and check if you are getting mail daily - for example, ...
As far as I know, there is no free one.
Suppose someone gives you a list of 1 million email addresses with some metadata and says: "These are our registered users, I've anonymized the personal information, now check the accuracy of this data, in particular check if the email address is still valid". What can you do?
You can check against someone else's ...
Not a direct answer to the legal question, but...
If you send any unsolicited email then to prevent your sending address/domain being marked as a spammer, you should use an emailing service. Once you are marked as a spammer, which is based on people putting your email in the spam folder, then very few of your emails will get through to inboxes.