I'm not really sure what PG had in mind -- his comments are a bit vague, although perhaps a good starting point for a conversation.

I think if you just use this system for awhile, tons of ideas will come out. In fact you can generate a lifetime of work from it :) PG always talks about making something for which you are the customer.

EverNote is of course a company in this space. I used them for awhile; it's nice that they have iPad clients and the like. But I found their products to be a bit complex.

Here are some random things I want to fix:

- mobile access. In the past 10 years, this was a huge change. My Wiki is basically read-only on mobile devices. I have to go back to the desktop or laptop to really write anything. This is OK but I imagine there could be some mobile interface for typing or speaking and hyperlinking. EverNote partially addressed this.

- Data model for bookmarks. Actually I sort of poo-pooed the journal model in favor of a Wiki. But to be honest I've realized that a lot of things are links which I find on HN and the like, which need a date, "read" tag, and free form notes. It's basically delicious / pinboard, but with an emphasis on comprehension and connections to previous ideas.

- Unsurprisingly, I've found the need for a spreadsheet-like data model for finances, and certain kinds of research. Yes, I could just use a spreadsheet, but the hyperlinking and web hosting is huge. I use Google Spreadsheets now but would like something a bit faster and more under my control.

- I like having these notes as my data for all time. Delicious came and went in the last 10 years. A lot of the value for me is that it's personal, and not tied to any cloud service, which conflicts a bit with current business models.

- Search. Right now I have a fast full text scan with sqlite. I've wanted to write a script that would fetch bodies for all the links, put them in a full text indexer, and let me search quickly there. And maybe take screenshots with PhantomJS.

- Information curation. I have over 2000 pages now, and sometimes I probably forget to link back to stuff I should. I create duplicate pages by accident. This should be solveable with some hints.

- Stats on which pages I actually read. With 2000 pages, I need some kind of ranking now. Some are ancient/obsolete.

- Mirroring of my content hosted elsewhere... e.g. it would be nice to suck down my comments from HN and be able to search them later. I had a lot of good conversations on UseNet way back that I wish I still had :)

Not sure if any of these are good business ideas, but those are my thoughts :) A lot of them are partially covered by existing products. But the the thing I am suggesting is for particular programmers to build the particular thing for themselves. Everyone's preferred mode of information organization will be a little different. It's nice to have something you made for yourself. I think it's a good exercise, because you can start very simple and gets you in the feedback loop of product use / product design / implementation.

But it's possible it could lead to a company. For me it to led to some other technology, like a web server container variant of WSGI / CGI (both of these have problems). And backup / deploy stuff.

One problem is that companies are incentivized to go "wide" to acquire new customers. But I want to go "deep" into my own use cases. There are certain problems you only hit after you have 1000 pages. Probably 99.9% of EverNotes customers don't have that volume of content.