Thanks for your insights, arthabaska.
Are there any websites in particular which you can recommend? Might be a good inspiration at least.

I suppose if there really is no software product you can use locally (which, to be honest, surprises me, seeing as the frequent flyer community seems so vast) this might be a niche that's absolutely worth exploring, if, as you say, one is "programmatically inclined"...!

Thanks anyway!