And Fugu is also known as SFTP, SCP and SSH Frontend.
And the word Fugu is originally taken from the pufferfish in Japanese language and the dish prepared from it, it said that fugus is genus Takifugu species. (Wikipedia)
Why you need Fugu?
install deb files from Cydia, this SFTP client is one of the required stuff before going into the installation.
And Fugu is a free Mac OS X SFTP, and offers many features you can utilize. And then has SCP file transfers support, also you are able to make secure tunnels via SSH.
You can learn more about Fugu from its official site and then download this SFT client for free under BSD-style license.
Head to Fugu to download it.