We have developed a pipeline tool to find giant virus sequences in metagenomes. It called Giant Virus Finder and are available from the site of our group: Giant Virus Finder. This is the only tool specialized to find giant viruses.
Using it we have found giant virus sequences in metagenomes sampled from the saline desert of Kutch (Giant viruses of the Kutch Desert) and from Antartic dry valley (The "Giant Virus Finder" Discovers an Abundance of Giant Viruses in the Antarctic Dry Valleys). These results are important because nobody have found giant viruses in soil samples of a dry environment before us.
A very interesting side product of the Giant Virus Finder is Giant Virus Toplist.
If you want to know more about these interesting organsims I also recommend this site.
I welcome any comment, question and suggestion. This will be the official support topic of the tool.