For anybody with an NFC (Near Field Contact)-compatible phone (such as my new Google Nexus 5), you can use the this little app — Tag Info Lite to read Myki cards.
Not that it’ll tell you very much — see below. All the actual useful information appears to be encrypted.
Apparently in some parts of the world an unencrypted copy of the card balance/status is also stored, allowing apps that will let you check your balance. For instance Farebot works with cards from Seattle, San Francisco, Singapore, the Netherlands and parts of Japan, and Travel Card Reader looks similar.
Shame Myki doesn’t appear to have this option, not even in PTV’s own apps — though I guess in theory they and/or Keane could do it, given they issue devices to Authorised Officers to do card checks.
With the old Metcards, you could easily see the expiry date(s) as it was printed on the card itself.
This is an opportunity, of course. As more phones include this technology, perhaps a future (hopefully minor) upgrade could allow people to check their card balance or fare expiry in this way.
(Some apps claim to do this with Myki, but what they’re really doing is checking your online account, which is not necessarily up to date — the card is the point of truth.)
Oh, and here’s what I get from a Brisbane Go Card: