I have just returned from the Seychelles last month, and can tell you that while traveling there on a shoestring is tough, it is possible (if you're willing to forgoe a few luxuries).
Here is how one can save a few Rupees:
* Take the public busses. A cab from the airport to our hotel (Hilton Northolme) would have been about 20-30 Euros. A bus (with one transfer in Mahe) was about 1Euro for the two of us. Sure, the bus is hot and crowded, but it's a unique and fun way to travel (and to mingle with locals).
* Eat outside of the resorts. We had a great meal at the Boathouse (Creole buffet). With a few Seybrews, it cost about 15 or so Euros per person. The same meal at our resort would cost about five times that price
* Change money on the street. For the record, this is ILLEGAL, but pretty prevalent. The official rate when we went last month was somewhere near 5.5 rupees for one $USD. We were able to get 9.5 Rupees per dollar on the street with no problems at all. Note that you can't use rupees to pay for touristy things (hotel, car rental, excursions, etc), but you can pay cash at restaurants, bars, souvenir shops, market, etc
* You can apparently rent an apartment/house/room instead of a hotel, and save money that way. Or, you can chooose the route we took and use your points (Hilton in our case) for your stay. Otherwise, you could spend a fortunte on lodging (our hotel would cost $700+ per night if we did not use points).
Hope this helps. Let me know if you have other questions.
Bostonbali