Many experienced online casino and poker players outside of the USA will have heard of, and probably use, the Neteller eWallet (WikiPedia) service, a free online banking service that pretty much every online casino makes use of to receive deposits and send out cashouts. For those that don’t, it’s relatively easy to set up and once you are accredited (requires scans or photos of ID being sent), you can use this to send and receive money to and from online casinos, poker rooms and sportsbooks. It also comes with a Mastercard prepaid card and the ability to transfer to a nominated bank account.
USA Players
The Casino Action group used to provide these but unfortunately they went under in March 2008 and, although they have since been bought out by Casino Rewards, the latter doesn’t have the Instant Neteller payments. Therefore, for the US market the options are no more - the closest you will find for the US is iNetBet (RTG) who process same day or Club USA (also RTG) who do overnight processing.
UK & European Players
In the UK and Europe, you could use the Microgaming casino from Canbet which allows Instant withdrawals to Neteller. Alternatively, while “instant” Neteller isn’t quite the right term, you will find that [Ladbrokes Casino] (Microgaming) does < 6hour withdrawals back to Neteller, and Blue Square also does processing quickly - usually same day.