Bitcoin is a peer-to-peer electronic cash system that is completely decentralized, without the need for a central server or trusted parties. Users hold the crypto keys to their own money and transact directly with each other, with the help of a P2P network to check for double-spending.
FileZilla is a multi-platform FTP program. The suite includes an easy-to-use client, which is similar to other popular FTP programs like WS-FTP or Cute-FTP, and a Windows-only server. The client supports various flavors of FTP and SCP, including FTP over SSL/TLS (FTPS) and SSH File Transfer Protocol (SFTP). The client also features IPv6 support, support for resuming and transferring files larger than 4GB, a tabbed user interface, a powerful site manager and transfer queue, bookmarks, drag and drop support, configurable transfer speed limits, filename filters, directory comparison, a network configuration wizard, remote file editing, keep-alive, HTTP/1.1, SOCKS5, and FTP-Proxy support, logging to a file, synchronized directory browsing, and remote file search.
KeePass is a light-weight and easy-to-use password manager that removes the need for you to remember many different passwords and makes it more feasible to use different passwords for each account. It manages your passwords in a secure database encrypted with AES and Twofish, which is locked with one master key or a key file.
KuickShow displays images using all available space, without wasting it with bars or menus. It also has smart automatic zooming which scales images according to size. You can use the integrated file browser to choose images, or navigate through a folder with the mousewheel or the keyboard. It also has fullscreen view and slideshow, and supports a wide range of image formats.
MuseScore lets you notate and compose music easily with your keyboard, your mouse, or a MIDI keyboard. You can print beautifully engraved sheet music or export it as PDF or PNG. You can play your score, transpose it, and save it as audio or MIDI file. MuseScore also supports MusicXML to let you share your composition with other scorewriters. MuseScore is often advertised as a cost effective alternative for Sibelius and Finale.
PeerProject is a versatile peer-to-peer filesharing client and file manager. It's intuitive and aesthetic while supporting many networks and features, including BitTorrent, G2, Gnutella, eDonkey, DC++, IRC, HTTP/FTP, and more. It's a mainstream fork of Shareaza p2p, for Windows and WINE.
Thunderbird is a total redesign of the Mozilla mail component to produce a cross-platform, stand-alone mail application using the XUL user interface language. It has many new features, among them the ability to customize your toolbars the way you want them. a new look and feel with a large number of downloadable themes which alter the appearance of the client, and the ability to add UI extensions.