Prompted by @markhawker via Twitter I had another look at the MedWorm 'enterprise design pattern'. Clearly it is essential that I find a way of ensuring that MedWorm's processing capability is used to maximum efficiency, to ensure that MedWorm can pay for itself as it grows. So I had another think about where most of the processing power is getting used up on MedWorm, and came to the tough conclusion that I will have to bring in a subscription model.
MedWorm will remain completely free to use, except for one bit of functionality, that of customized RSS feeds. At the moment there are (many) hundreds of RSS feeds for you to pull out of MedWorm that are precompiled every day, based on optimised queries for individual topics and data types. You can find them simply by browsing MedWorm - every page you go to has its own RSS feed - and these will remain free.
However it is also possible to create RSS feeds 'on the fly' from any query that you run on MedWorm. The problem is that the majority of queries that people run do not make good RSS feeds. For example, a search on the term 'breast cancer', without using the quotes, and without selecting the Exact Phrase search option on MedWorm, will return all records where either the word 'breast' or the word 'cancer' exist. When viewed by order of relevance when running the query this does not matter, but pulling out an RSS feed for that query is pointless, since not every record that you will see in your feed will be relevant to breast cancer.
This may seem obvious, but the fact is, no matter how many times I tell people, most will still continue to pull out useless RSS feeds. Following which will likely put those feeds into a feed aggregator, or worse still automatically generate webpages from those feeds, which will mean they re-run those useless queries on MedWorm every day (or if they don't cache their data at worse every few minutes), and probably pay no attention to the feeds, and fill up the Net with more useless junk - at the same time eating up MedWorm's valuable processing power.
Worse still, there are a lot of sites looking to create the maximum amount of meaningless junk that they can in order to run GoogleAds alongside, which at times pull out hundreds of these useless feeds from MedWorm, of which some of them at times use very 'unsavoury' search terms to create their feeds. I block these servers whenever I notice them, but it is a waste of my time to try to keep on top of these.
So in about one month's time I have decided to limit this 'RSS on the fly' functionality to premium members only, who will have to pay a monthly subscription. Not sure how much yet - suggestions welcome - I'm thinking about $5 a month - after which I will monitor to see which users are really hammering the server and possibly bring in a higher subscription level for unlimited use for those developers that are pulling out hundreds of feeds each day.
In doing so I'll be able to give you all a better service, faster, with more frequently updating data. I'll also hopefully avoid MedWorm going bust, so that we can all continue to enjoy the service for years to come.
If anyone is hard up, or from a developing country, and can't afford to pay, but has a real need for the customized feeds, they will just need to drop me an email and I'll give them free access anyway if their needs are justified.
Bringing in the subscription model will also encourage people to browse for feeds instead, which will likely be of much better quality for you to use anyway.
I hope you all find this acceptable. Feedback welcome! It is important that I get this right as I am primarily building a service that will be beneficial to all of society, and fair, not trying to get rich (although if I do one day get rich in the process that would be nice!).