According the the highway code , drivers should allow at least 1.5m, or 5 ft, when overtaking a cyclist. Cyclists are also not obliged to cycle in the gutter by the road: in fact cycle skills teaches a more central position for visibility and safety.
I am cycling to and from work as it's the right thing to do environmentally. Public transport is pretty limited unfortunately. Around half of drivers pass too close, often within a foot and at speed. I have noticed that it is often German car drivers.. I also had a driver intimidate be by coming up close behind me and sounding the horn because I wasn't in the gutter. In this occasion it was approaching a junction with no safe space to overtake.
I have also had a car reverse into me when I was still in a queue of traffic. It sounds simple, but drivers need to look in their rear view mirror when reversing.
To anticipate common moans people have about cyclists: I have third party insurance, I have done cycle skills training, and have a driving license so am aware of the rules of the road, and I stop at red lights.