I've always found ironing very relaxing.
No matter how irritated I am, 5 minutes into the ironing session and I find myself relaxed and, as funny as it may sound, in a kind of "zone".
The repetitive motion of the iron over dress shirts and trousers always helps me drift away and rarely do I finish such ironing session without some novel ideas. But the trick is to be able to capture these ideas and use them, or they simply float away as quickly as they are generated. So after losing some really great ideas generated during ironing and simply forgotten later, I now make sure I have my notepad or notebook close at hand. Try it the next time you iron (or do the dishes, or whatever boring, repetitive household choir it is that you do).