Trillian v5 — программа-мессенджер для Windows, Mac OS X, Apple iOS, BlackBerry и Android, созданная компанией Cerulean Studios. Поддерживает многие распространённые протоколы обмена мгновенными сообщениями, такие как AIM, ICQ, Windows Live Messenger, Yahoo! Messenger, IRC, Bonjour, Jabber, Skype и др.

Trillian v5 — is a fully featured, stand-alone, skinnable chat client that supports AIM, ICQ, MSN, Yahoo Messenger, and IRC. It provides capabilities not possible with original network clients, while supporting standard features such as audio chat, file transfers, group chats, chat rooms, buddy icons, multiple simultaneous connections to the same network, server-side contact importing, typing notification, direct connection (AIM), proxy support, encrypted messaging (AIM/ICQ), SMS support, and privacy settings. Trillian provides unique functionality such as contact message history, a powerful skinning language, tabbed messaging, global status changes (set all networks away at once), Instant Lookup (automatic Wikipedia integration), contact alerts, an advanced automation system to trigger events based on anything happening in the client, docking, hundreds of emoticons, emotisounds, shell extensions for file transfers, and systray notifications.