i was thinking about this concept being a rather superstitious kind of person: at what point do "these mini obsessions" become actual spells, your conscience efforts...imbueing them with some power? Is it possible?

Well, if someone truly believes that if they see a magpie that they will have bad luck, then they will view anything undesirable that happens to them following that as bad luck.

Voodoo has also been proven to work, a form of self hypnosis.
Faith is a powerful thing

an example i'm thinking of is gambing - kissing the dice, wishing really hard, little tricks that supposedly help the process - i'd say they were simple spells.

same with rituals that sportspeople dabble in such as wearing the same lucky socks, putting them in the right order etc.

but then again, i see prayers and spells being almost the same thing whereas some people - particularly conservative religious people might find that somewhat blasphemous

*shrugs*

I like the 'to step under the ladder is bad luck'.. of course it is every time you walk under a ladder you increase the chances its going to fall on you. And when it does you going to get a group of people going 'Bad Luck Man'.

i don't think i have ever stepped under a ladder in everyday life.

i have when there was a point in doing so - for amusement. it didn't last long.

actually the ladder concept came from the belief of it forming a natural trinity and if you stepped beneath it you would break the trinity of the father, the son, and the holy ghost...I guess they's smite you or something...funny enough most of today's superstitions come from very christ retentive times...

When you sit down, draw in the energy and focus your will/intent. I guess it depends on the obsession or whatever. If you are convinced something will happen, then it probably will because you will subconsciously set it up so that it does. That's not magick, though.