After finished the online training on EC2, S3, RDS which I already familiar with, I finally received the remaining USD75 credit thru email from amazon. Many thanks! Sum up with the USD25 free credit that obtain by attending AWSome Day KL in cyberjaya, I accumulated a total of USD100 credit. Well, my monthly expenses on AWS is certainly more than this amount but I appreciate this marketing approach.   Thanks again to Amazon and I do hope your pricing can keep reducing from time to time as your scale of economy increase.