There was a proposed trade back in 2007...Kobe to the Pistons for Rip Hamilton, Tayshaun Prince and some draft picks and Kobe, who had a no-trade clause in his contract, vetoed the trade. He gave the Lakers a list of teams he was comfortable going to and Detroit was NOT on his list, Chicago was his #1 choice but of course that didn't happen either as he played his entire career with the Lakers.
But can you imagine if Kobe became a Piston? Would they have won another championship?