stresser.us - I don't see this as having much value. Maybe there's something you know that I don't. The only meaning I give it is "someone who stresses", and I don't see huge value associated with that.
hashdecrypter.com - Not valuable. It might be the name of a niche and possibly valuable software product, but any company selling a hash decrypter would not get much additional advantage from the domain, so it's not valuable.