I usually make concasse.
With a knife, carve an X into the top of each tomato. Drop into a large pot of boiling water for 20sec or so. Immediately remove them to a bowl of ice-water for 30-40sec, then peel the split/separated skins off.
Next I trim the vine end and halve the tomatoes. I pull out the seeds/membranes, and then dice the skinless/seedless flesh into whatever size I want. Takes a while the first couple times you do it, but then it just becomes routine, right down to washing the pot as the tomato skins contract in the cold ice water.
Nick ~ "Egg whites are good for a lot of things; lemon meringue pie, angel food cake, and clogging up radiators." - MacGyver