Hi Dave!
ACH // Check21 for USA and Canada works good as secondary option to CC processing.
EuroDebit for EU works great too as a secondary to CC.
PhoneBilling will not make you a fortune and may not be viable but is an option depending on the country. Of course do not use it for CC billable countries.
SMS billing, pretty much similar to above. Not a huge money maker. Though it does depend on your business model. If you're SMS billing per download, it could work out for you.
MicroPayment and e-Wallet systems can work for sure, but depends on the countries they are working in and their load options.
As Marc mentioned, uKash is becoming more popular as a payment option. It can be a good option for EU and Russia // CIS countries. Yes I have seen it working.
Everything has it's uses, it just depends on how you run shop and if it is going to worth the time, content exposure, bandwidth etc. I mean if you get an SMS sale and make $0.20, obviously you do not want that user having 30 days access to your content right
oh and then splitting that with the affiliate etc lol. So it really just depends on what you want to do.
Good luck and hope to have helped at least some.