Here is an interesting fact:
everytime Sangakkara has scored a double century Sri Lanka has won the match.
Sangakarra has six doubles not including this one, which is just as well because this match hasn't resulted in a Sri Lankan win so your "interesting" fact is technically inaccurately worded but might escape being wrong if Sri Lanka do win
Sangakkara - make mine a double
230 vs Pakistan (01/02) - WON : Pakistan had been bowled out for 234 by Vaas, Fernando and Murali. Vaas and Murali then took four wickets each as Pakistan only just forced Sri Lanka to bat again
270 vs Zimbabwe (04/05) - WON : Zimbabwe were skittled for 228, Sri Lanka racked up 713/3d and Murali helped himself to four wickets to secure a massive innings & 254 runs win
232 vs South Africa (04/05) - WON : Sri Lanka notched up 470 before Jayasuriya took 5/34 and South Africa were all out for 189. Sri Lanka batted again before again dismissing South Africa for less than 200 with Vaas taking 6/29
287 vs South Africa (06/07) - WON : South Africa were skittled for 169 with Fernando and Murali taking four wickets apiece, Sri Lanka racked up 756/5d before South Africa were bowled out for a valiant 434 in the last innings with Murali taking 6/131
200no vs Bangladesh (07/08) - WON : Bangladesh were annihilated for just 62 with Malinga and Murali (the chuck brothers) taking four cheap wickets apiece. Sri Lanka didn't bat for very long in making 451/6d before Bangladesh fell one short of 300 second time around.
222no vs Bangladesh (07/08) - WON : very next Test Bangladesh were bowled out for 131 with Murali taking 6/28, Sri Lanka posted 500/4d before Murali took 6/54 and Bangladesh didn't make 200 second time of asking either.
So three against the minnows of Zimbabwe and Bangladesh. Shame he hasn't carried on keeping, is arguably one of the best batsmen keepers along with Flower and Gilchrist, both of whom only ever managed one double (although Gilchrist batted down the order, Flower batted in a weak side)