Ask HN: Best software for schematics/diagrams?

None of these earns the bonus for being free, but perhaps you could take a closer look:

* Microsoft Visio - I've never actually used it, but it used to be the de facto standard back in the old days when nobody ever got fired for buying anything Microsoft :)

* http://lovelycharts.com/ - this is an online diagramming app built on the Flash platform (I can't help mentioning that :), very cool stuff. However, I've never used it for anything but the simplest diagrams, I suggest that you try it yourself.

Based upon my experience: Open Office Draw is quite good. For greater power, you could consider InkScape. Dia is also good if you have the time to tweak to your requirements. I end up using OO-Draw for 80% of my diagrams and it interfaces with OO-Impress.

GIMP will work but might require more effort than you want to spend.

Will anything in Open Office do this?

omnigraffle comes to my mind, you can use pencil maybe, try balsamiq and the like.... mindmaps is another thats very generic in nature and has got gr8 utility.