You may take a look at this Website: https://www.europe.f-secure.com/v-descs/checkin.shtml
or this: http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=TROJ_CHECKIN.B

Maybe www.lavasoftusa.com (AD-Aware) or http://beam.to/spybotsd (Spybot) are usefull Programms for you.