In our site
http://www.entermediaplus.com
the solution is to use certain valued gift card like physical goods, designated as tax-free, classified as gift-voucher (instead of product). Then setup another shipping method with free cost for shipping with the weight bound from 0 to 0 (I guess you need to setup all other non-gift card products to non-zero weight. This seems work. Anybody has a better way?
Regarding to separation, it may be achieved to modify category block temperate, but I used a category named "__________", seems did the trick.
Please share your tricks and critics, so we can make our sites look more professional.
Thanks.
EP