Double Choco Latte provides basic project management, work orders, and call center tickets. It supports the following features and concepts:

Work Orders - Use for tracking history of almost anything: bugs, requests, maintenance, project tasks.
Projects - Include hierarchal support so sub-projects can be created. Parent project's statistics include all child project stats to provide an overall status of all projects.
Call Tickets - Use for contact with clients. Self-timing.
Time Cards - Time taken on a work order to accomplish an action. Multiple time cards can be input for a single work order.
Attribute Sets
An attribute set consists of: Actions, Priorities, Severities, Statuses.
Each product can support its own attribute set for work orders and tickets.
Accounts - Client based tracking
Personnel - People involved in the projects, including hierarchal support
Departments - To "categorize" personnel
Severities - List a bug's severity level
Priorities - Ranks bugs by priority
Statuses - Tracks bugs by status
Sequences - Related Work Orders carry the same Job Number and incremental sequence numbers. Can be used for projects.
Products - Obvious, but also can be assigned a person to "report to". Useful for product managers to track what they're responsible for.
E-Mail notification via watches.
Notification for statuses: Open, Close, Change
Optional notification for any activity
Can watch a product or project and receive E-Mails for their respective work orders
Can watch a specific work order.
Can also watch tickets in the same way, with the exception of projects.