My MIL (and sometimes SIL) will pop round unannouced. It can be anything up to 4 times a week and its really starting to annoy me. Also, if I don't answer the door quick enough, she looks in my living room window!
I find it very rude. Am I being too sensitive? She will sometimes phone, but if I'm out/busy/sleeping/dont hear it, she will come round anyway.