CrushFTP Features

Full scale FTP server.
Cross platform. If you can run Java 1.4 or better, then you can run CrushFTP. (MacOS X, Windows, Linux, etc.)
Inexpensive commercial quality product for a shareware fee.
Fast, multithreaded design.
Multihoming support. Virtual servers for multiple IP's, or multiple ports on an IP, or both.
Event actions that are user customizable. They can generate emails with real-time data of what happened. You can also perform file I/O.
Resume download/upload support...even for MacBinary transfers.
Complete GUI remote administration from any machine that can run CrushFTP. (Your remote GUI controls the Server.)
Intuitive, built-in user manager for administering user and group accounts.
Built in log viewer is updated in real time as the server is running.
Directory permissions per directory. All directories can have different read/write/view/delete/resume/rename/make dir permissions/etc.
File permissions per file. All files can have different read/write/view/delete/resume/rename/etc.
Directory quotas. Every directory can have a quota applied to it, or inherit from the parent directory.
Virtual Directory support on any platform. Design your own directory structure for a user when they log in.
MacBinary III encoding on the fly when a user has turned on MacBinary (MACB E) and is downloading a file with a resource fork. Also, uploads that are MacBinary files are stored as Mac files.
Bandwidth limits on uploads per [user/group/server].
Bandwidth limits on downloads per [user/group/server].
Idle timeout for auto-disconnect per [user/group].
Maximum login time allowed per [user/group].
Maximum simultaneous logins allowed per [user/group].
Maximum logins per IP for a [user/group]. (e.g. 100 anonymous logins, but only 2 from the same IP)
Allow/Deny IP restrictions for logins per [user/group/server]. Supports IP ranges for deny and allow.
Max download amount per [user/group] for each login session. (e.g. after 10mb's the user cannot download till they logout and then login again)
Server queuing for downloads/uploads. No other FTP server has this feature.
Day of week restrictions per [user/group/server] (e.g. Sun, Mon, Tues, etc.)
Time of day restrictions per [user/group/server] (e.g. login between 10 a.m. and 11 a.m. and between 4 p.m. to 10 p.m.)
Group inheriting for users, along with ability to override any part of a group setting for a particular user.
Spying on connected users. See all their log, current dir, bytes sent/received, transfers speeds, login time, login IP, visual progress bar for downloads, and estimated time left.
Download ratio per [user/group]. Both can be temporary per session login or permanent.
Incredible server statistics, such as last login date, time, IP, current total server bandwidth usage (bytes in/out), files downloaded/uploaded, graphs for bandwidth utilization, etc.
SITE commands for remote administering from an FTP client. Each [user/group] can be limited to what commands they can issue.
All server messages are customizable, along with nearly everything else in the server.
Server variables can be displayed to users just by putting the variable in "%"'s. (ex. You are login # %login_number%.)
Soft server stop won't kick users, but still stops the server from new connections.
Customizable logging options allow you to control what gets logged to both the server window and log file.
Custom time of day restrictions for things like bandwidth, and maximum users.
FXP protection just in case you don't want users doing FXP transfers.
Reserved ports can be blocked to prevent the FTP bounce attack.
Filtering of filenames for uploads, downloads, lists, and renames.
Temporary bans for users.
Hammering protection that will ban a user.
Temporary accounts that can be set to auto expire after so long, or be automatically deleted!
Users behind a router/firewall can have CrushFTP auto discover their real IP.
Log rolling allows logs to automatically be archived, or deleted.
Supports a range for what PASV ports to use so that users behind a router/firewall can map those ports through.
Can listen on multiple ports.