Find the area of the triangle below.
[asy] draw((0,0)--(2sqrt(2),0)--(0,sqrt(2))--cycle); label("$2r$", (sqrt(2), 0), S); label("$r$", (0, sqrt(2)/2), W); label("$\sqrt{10}$", ((2sqrt(2),0)+(0,sqrt(2)))/2, NE); draw(rightanglemark((0,1),(0,0),(1,0),5)); [/asy]
