things that make you go argh

in order of occurrence:

1. vacuum cleaner spews dust all over the room, despite what is supposed to be a good filter-bag;
2. vacuum cleaner also spews that horrible burnt rubber smell, despite having dismantled the beater bearings down to individual balls, cleaned out all of the hair, and regreased them;
3. malfunctioning floor fan cannot be disassembled, as two of the six screws are not just Torx, but security Torx (with the pin in the middle);
4. discover the above screw situation only after losing one of the other four (normal philips head) screws inside the case.