I did it the other way round - came in late to avoid the traffic (which made the bus journey twice as long if I came in early) , and stayed late. One day I got a message that the big white chief wanted to see me (I was a trainee something or other, he was in charge of Nelson Research Labs, with a few hundred people doing research under his direction) so I went with some trepidation to brave his secretary (a veritable dragon) and gain access to the inner sanctum. He explained that people in one of the divisions were commenting unfavorably on my late arrivals. I explained that I was staying later tocompensate. He responded that he already knew that, and so far as he was concerned it wasn't a problem, he had asked the security staff about my hours and the conclusion was that I was putting more hour in than my contact required. Therefor he wanted me to go to the payroll office and give them details of my working hours for the last few weeks so that they could provide the appropriate monetary compensation for the extra time I had put in. At the time I was carless, and the result was that I acquired sufficient pennies to buy a used car and get the required insurance for it, so now I could contribute to the traffic problems if I so chose. What it mostly got used for was travelling to see my parents or my girlfriend and attend the regular computing seminars at Cambridge U's maths lab (which counted as work, so the company paid my travel costs).