Not to HTML but pdftoword.com has a fantastic online converter to .doc (also does .rtf) This may be a useful path for you. All the best

The great application idea needs to be your driver. I suggest you take the leap of faith and believe that if the application you create for yourself is great then others will think so too. Next create a place, like this, where your users can ask questions and place feedback. The camaraderie generated from such interaction could well be all the satisfaction you are looking for. If this approach gets you motivated to start, build the application such that you can decide on release date which route to take regarding payment. While difficult to manage you could progressively move through all of the various payment methods with successive versions as the users assist you with improving the application as bugs and features are addressed. Sadly this may alienate your loyal following though. :( In the end your popular application may not directly generate the revenue but the place that hosts it may pay you a cent for every download that is free to inquisitive surfers. Would 100,000 cents be of interest? Note that without the forum arrangement mentioned above this payment would, in itself, not be satisfying. All the best.