I'm in the something else category.
I'm lucky - I don't need to carry a laptop, and I can leave most things at the office to minimise what I need to carry.
I used to use a ventilated rucksack, then I switched to a frame triangle bag in addition to a saddle bag. The bike repair stuff goes in the saddle bag.
I have one triangle bag on each bike and I think they are great. They are waterproof, and they are not expensive (about £12 IIRC) or heavy (<300g IIRC). Most other cyclists hate the look of them, at least on this forum and in my office. Suits me as it keeps them cheap

(although I've not yet had to replace them - they seem really well made and I've had them over a year).