Just some brief notes on my voting experiences with absentee ballots in Maryland.
The instructions for requesting a ballot appear on the state's Election Board website. There is a PDF form to print out and return, but interestingly you can submit the form via email or fax, and you can request the ballot being sent to you via email. They even allow the ballot to be sent to a different mailing address but it was the email option that interested me the most. You only need the voter's name, address, date of birth and party affiliation to request a ballot (you do have to sign). To request the ballot I did just that by getting the PDF form and returning the signed version via email.
About 2 days later I got an email pointing me to the Maryland voter registration status website, where people can check on their voting registration status. To access the site, you need to know the voter's name, date of birth and zip code. Once logged in, there is a link to the absentee ballot which requires knowing a tracking number which was included in the original email. Once in, there are several PDFs containing the ballot, a prefilled oath form to be signed by the voter and PDF containing the envelope information. The tracking number is included on the oath and the envelope BUT not the ballot itself which has no marks identifying the voter.
What was a little concerning is the ballot itself - it referenced two charter amendment questions, the full text of which I could not find online. I eventually found both of them on the Baltimore City Council's legaslative system but it took a lot of digging (see this, this, this and this). Question A proposes letting the city borrow money to fix the school system as a non-lapsing (permanent) fund which can be funded by donations or ordinance of estimates assignment. It is interesting to note that the city's Department of Finance opposes this amendment and the Department of Law raised some important legal issues as to whether the amendment itself is even legal. It is also interesting to note a somewhat weird power point presentation from the school system. All of these documents are available here. The second question lowers the age requirement for council members to 18 from 21, and requires people to be registered voters in the city, as opposed to be registered voters in general.
The ballot and oath must be returned to the Board of Election via postal mail. Once counted, supposedly it will show up in the same online system allowing the voter to check that their vote was counted - something conventional voting does not allow (although people are trying).
The most worrisome aspect of the whole process is security - once you know the basic registration information for a voter, you can then request a ballot online and mail it in. What would make it more secure is that the voter tracking number should be sent via postal mail instead of email to the registered address or at the least a post card saying that "someone requested a ballot for you". While the Board of Elections may match signatures, it would be trivial to get copies of registration records and signatures just like the Board of Elections plans to do with petitions against illegal immigrant in-state tuition several months ago.