what do you know about Cost control ? How can you apply it in your general work ?

From my point of view the cost control is very important part of work of any thorough manager. And it is "very simply" :-).

I have a yearly budget divided into twelve period. Every month I need to do check with financial department, if I am still in terms of the budget or not. If yes, no problem then. If I have savings, I can spent them or I can save them for the future. If I am not in the budget, in next period I need to save the missing amount, or use the part of amount save earlier, or to be killed by my boss :-)

Of course it is not so easy, it is really though fight every month. But with a good budget preparation and with regular monthly cost control the successful budget delivery can't be a significant problem. 

The process or activity on controlling costs associated with an activity, process, or company.
Cost control typically includes (1) investigative procedures to detect variance of actual costs from budgeted costs, (2) diagnostic procedures to ascertain the cause(s) of variance, and (3) corrective procedures to effect realignment between actual and budgeted costs.