Thanks to MatSav on uk.railway for the heads up, this rather good
offer has come to my attention - I thought it deserved a thread of its
own, so I hope he doesn't mind me starting this one (which is x-posted
to both uk.transport.london and uk.r).

National Rail are running a promotion for Oyster card and Freedom Pass
holders for days out from London - with substantially discounted Off-
Peak Day Return fares, and in some cases Off-Peak period Return fares,
to a pretty wide range of destinations as far away as Bristol,
Cardiff, Norwich and Crewe (the last on LM trains only). The offer
runs for a month from Sat 26 June (tomorrow) until Sun 25 July.
http://www.daysoutguide.co.uk/oyster

The return fares are priced at the following levels: £5, £10, £15 or
£20. The journey is supposed to start from a London terminus station.

Critically to take advantage of this you need a voucher for each
journey which is printed off from the website - this is actually a
personalised voucher, for which you're asked to hand over some
personal information as well as specifying the date and destination
(with origin London terminal if there's a choice) of the intended
journey, and are also asked for your Oyster card number, at the end of
which you're presented with a custom generated voucher to print off
and present to the booking office alongside your Oyster card / Freedom
Pass.

Obviously one of the motivations underlying this offer must be the
TOCs desire to capture information for their customer/ marketing
databases. The requirement to submit one's Oyster card number
undoubtedly pricked my ears up somewhat, as I'm rather curious as to
how they'll chew over this information. However, if one has an
unregistered Oyster to hand, then dare I suggest for the purposes of
this offer one could be who one wants to be. (TfL looks like they
might well get a look in on the data, but you wouldn't end up
registering an Oyster card by proxy simply by partaking in this
promotion.)

Anyhow regardless of such considerations, this looks like a nifty way
to get out of town out of town for a cheap trip, for the next month at
least!

The blurb does say that you should use your Oyster to reach the London
terminal station, but I very much doubt if the booking office check
this - if they did (which would astonish me), then you could always
nip out and touch-in on a bus! Oh, and TfL Staff Oysters are good for
it as well, it seems. And the drop-down list of Oyster card types has
an "Elite Athletes Oyster photocard" as an option, which is a new one
on me - anyone know more?

Actually, whilst trying to search for info on the above, I found an
internal rail briefing document about this offer, hosted - for
whatever reason - on this "Penalty Fare Appeal Support" website...

- their blog post on the offer is he
http://www.penaltyfareappeal.co.uk/wordpress/?p=1219

- the internal briefing document is here (PDF):
http://preview.tinyurl.com/33qyz6j