Though this isn't exactly being a reseller of an ISP, have you ever thought about being an Optical Transit Provider? This way you may resell bandwidth to others. Say you get your own space in a data center with your own cage etc. Now you can become a transit provider ie: sell 10MBPs of bandwidth, 100MBPs, 1GBPs etc it would all depend on what your initial backbone is. Nevertheless, if you would want to provider Internet Services to people in their home then this is a totally different story.
Nevertheless, as a Bandwidth/IP Tranist Provider you can make some serious money, however, it's required that you have some money to start off. Either way, being an ISP reseller also includes having the funds.