Thanks Howie.  Hopefully someone can make good use of them.

Hi, thanks for that info – i need a return from gatwick to stansted; do you think i should take advantage of gatwick express discount and then find my way to stansted once i’m in london or do the following:
 
Cheapest Indirect Route Via London[=“verdana, arial, helvetica, sans-serif”]
The cheapest option via London is significantly cheaper than the direct National Express Gatwick to Stansted bus. This cheapest option is also no slower than the direct bus.

The route uses the National Express Stansted to Stratford coach service that runs every 30 minutes between Stansted and Stratford. This takes around an hour.
Between Gatwick and London Bridge Station use the First Capital Connect train that runs several times an hour from Gatwick. This journey takes around 30 minutes.
The Jubilee Line of the London Underground runs every few minutes between London Bridge and Stratford taking around 20 minutes.[/]

To me it’s a toss up between the way you described and the gatwick express to victoria and then the express shuttle from victoria to stn. The direct service is always an option but the joys of the M25 make it extremely unpredictable!
cheers
howie

Sadly both codes have expired will update the thread in the future when needed.
cheers
howie

It pays to remember that discount codes for gatwick and heathrow are normally only a click away.

[note: spam link disabled by Don]

Realizing this thread is old, dug up by a spammer (link removed from post above), but here’s my tip:

Between Luton, Stansted, or Gatwick and central London
www.easybus.co.uk