Bit by bit, I have watched prices for household "robots" come down until it now made sense to bite the bullet and buy them.
So far we have
A Roomba vacuum. Bought as factory second for half price (with warranty), it cost us Australian $350 and was instrumental in convincing DH to get rid of the cleaner, which had previously cost $90 a fortnight. Our floors are polished concrete throughout and the robot does very well. We raised our IKEA Kivik sofas by putting them on legs so the robot actually does better than we could by vacuuming all the way underneath. I still mop the kitchen once a week and rest of the house once a month (skirting boards etc).
A Thermomix tm31. I sold my diving, snow boarding and motorcycling gear after having a baby and the proceeds were enough to get a two year old TM31. It makes great yoghurt, Gluten Free bread, risotto, Sorbet. Of course you can prepare all of these the traditional way too but the TM does make it easier with a baby. So far, it looks set to help us keep food costs down as I head back to work. DH loves it.
A massage chair - got it for A$200 from a nail salon that was closing. I use it as nursing chair and get a back rub at the same time. Getting a massage would be $60.