Just a credit crunch thought, but some of us don't like cheques sitting ideal. A cheque that is cashed up2 a couple of weeks after I have posted it, I can cope with, but a cheque that is going to be cashed months later isn't a good idea. Instant transactions are the norm now and it is so easy to forget that a cheque was written after say a month.
Many of us donate to WMF anyway, how about if we can prove we donate we get an associate membership without voting rights if we send in all our WMF paypal receipts? Although associates would have voting rights on constitutional matters.
Michael