OK, I'll be the first to admit that mosquitoes are NOT COOL. Besides being extremely irritating and discomfiting, they carry diseases and in many parts of the world are responsible for tremendous loss and suffering.
But mosquitoes can also be an aid to spiritual growth. You can ponder the mysteries of creation -- why would God want a world with mosquitoes, which have been part of the landscape for 30 million years? When they bite you, you can pray for people in parts of the world where malaria and other mosquito-borne diseases add to human suffering. With the exception of widely scattered West Nile cases, our mosquitoes will not make us sick. Others are not so fortunate. Or you can think of them as God's own way to mortify your flesh -- teeny tiny hair shirts as it were, to disturb your comfort level and remind you of your dependence on God.
But my favorite way to use the mosquito for spiritual growth is to practice compunctio. This is a term coined by St. Gregory the Great in the sixth century. It means the sudden sense of wrong-doing, the "puncturing" or sharp, sudden stab in one's conscience after one realizes one's sin. This quick piercing of the heart is good for the soul's growth, because it immediately turns one back in the direction of God.
So each time a mosquito punctures your skin, take an instant (before smacking the little sucker ...) and examine your conscience. If you are pierced by your own knowledge of falling short, release it to God, turn back to God, find yourself in the forgiving and loving arms of God.