I know a few
First, me: I never use too much cooking oil, even if I spend more on a bottle of beer than all the oil I use in one month.

And I almost always turn off the light when I leave a room while shamelessly running 2 computers 24/7, having the TV always open in the background.

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One friend of mine decided to redecorate his house. One worker he hired told some other friend that once they were looking for him around the flat (not very big) and finally found him eating in a closet. You know, to avoid having to be polite and inviting them to grab a bite.

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A few years ago, on my birthday I was paying drinks for 10 or more friends. The rule was I was paying for booze while they were paying for their own food.

After boozing for some hours the place was closing down and they gave us the bill. I obliged for the booze and some friends coughed up the money for the food. However, nobody cared too much and the tip grew quite large.

Then this other chap decided to solve the issue and extracted some money for the cab ride. Funny thing is he wasn't even involved in the bill, so it was not like taking his part of the tip back.

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I lived for a while with 3 other people in a rented flat. I shared a room with a salesman, one the tightest people I've ever seen.

Basically, he never spend money on food, as his family sent him packages every week. The only expenses he had were rent (very small at the time) and the daily beer and bread.

One day he managed to get a raise. What did he do to celebrate? Brought home beer, bread and some canned food (tuna).

Later, his girlfriend managed to score a free holiday: 2 weeks at the seaside, everything payed by some NGO or youth organization (well, everything except his daily beer, but he was buying it anyway). His reason to pass: they were getting back on a Sunday, which was bad because of him not being able to get the package from the parents, thus being forced to buy food for a week.

And he was 31 at the time.

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Actually, I have a long list but I'm too lazy to write it down.
(randomset, Wed 29 Oct 2008, 0:46, Reply)