Iota is a relatively new currency that has no transaction fees and doesn't rely on blockchain and miners.

Every transaction requires a user to verify 2 transactions by users. Essentially everyone has to "mine" a tiny bit and thre are no mining rewards since IOTA has a fixed supply. This is similar to the idea I talked about in a post from last year:
https://steemit.com/bitcoin/@camb/decentralize-it-eliminate-mining-pools-force-to-mine

Instead of a blockchain, IOTA uses what is called a tangle. In the tangle every node distributes part of the database instead of requiring nodes to download the entire database (blockchain). Even with this recent setback I still have a lot of faith in Iota. It's a completely new approach unlike a lot of other currencies that are just clones of Bitcoin with minor tweeks.

Every few months the IOTA networks gets rid of old garbage by creating a "snapshot" of the network. When a Snapshot takes place the network remembers the current address for every coin and forgets the transaction history before that. This keeps the Tangle database from getting too large and effectively also works as a "spam" cleaner.

Transactions on IOTA can also have zero value. (you can send 0 coins from address A to B)
Why would you want to? one example could be to attach a public note to the tangle. Since a zero value transaction still requires the sender to confirm 2 other transactions first it doesn't clog the network and the value of a transaction makes no difference to the priority it gets processed with.

IOTA was at a nice high point last month and is now finding a place somewhere in the middle like most other coins are at the moment. (might be a good time to get some now)

Holland has recently announced that they will be using IOTA for administrating legal documents.
https://oracletimes.com/netherlands-to-start-implementing-iota-miota-for-administrating-legal-documents/

BOSH has invested heavily in IOTA, seemingly planning on IOTA to be a big player for the coming "internet of things"
https://www.forbes.com/forbes/welcome/?toURL=https://www.forbes.com/sites/montymunford/2017/12/19/robert-bosch-venture-capital-makes-first-investment-in-distributed-ledger-technology