Just thought I'd mention this if you dont know already and if you have grubby cutting mats and are thinking of binning and getting new ones.
I went over to MDP yesterday and he gave me a cool little tip, I have 2 cutting mats which are a bit worse for wear, covered in crap and grime etc, he said just to give them a wipe with baby wipes, wait 10 minutes and give them another wipe etc etc until clean.
I have given mine 3 good cleans with baby wipes and it worked, took off a lot of crap to and also brings back the tac, not quite as taccy as a new mat but it did the job!