Take PCR for example. This is a method by which if one has even a single DNA molecule, it is possible to make a copy from each molecule in vitro , resulting in a sufficient amount of DNA to observe macroscopically. Furthermore, the tool used to cary out this reaction (a thermocycler) might be considered to be an assembler, since it carries out a series of specific chemical reactions and molecular assembly steps in order to produce the DNA output. However, since the purpose of this reaction is primarily to simply read the DNA sequence, nanotechnology will likely provide a more direct (and cheaper) method of reading the DNA, making self-replication a useful trick for the time being, but in general not the most efficient approach. Perhaps one day, it might be feasible to create a new life form from the molecular level, but seeing as we still know very little about the life already in existance it seems that we have much to learn first. Alias: Reproduction.