In the US, PayPal offers three way of linking a bank account with a PayPal account: eCheck, ACH, and Debit Card.
When payments are sent using the Debit Card method, a fee is applied because of the networks' fees. ACH is free and sends the money instantly (though it takes about 24 hours for the txn to appear on my online banking statement). I don't understand the eCheck system, however.
I understand the Debit card network and I loosely understand the ACH system - but what is an eCheck? I have a sinking feeling that this involves PayPal generating a fake picture of a cheque for the amount required, printing it, digitally photographing it, and using the photographic-cheque deposit system (I don't know how that works either).