What kind of features are you looking for?
In it's simplest form:
1. Offer digital product for sale
2. Provide potential customer with Bitcoin address for payment
3. Receive payment
4. Send digital good
There is also a forum where they do something of the sort called ogrr.com.
Well, if you want to sell a digital product with Paypal, ngcoders.com has a Paypal button called DigiSell 1.1.0
which works pretty well and is free.
Something like that would be cool.
Thanks for the link reference, I'll check it out.