This may have been referenced before, but everyone should eyeball this:

http://help.filemaker.com/app/answer...ro-11-advanced

similar specs can be retrieved by substituting 11 for 10...



an extract:

Technical specifications of FileMaker Pro 11 and FileMaker Pro 11 Advanced

Answer ID: 7541 Last Updated: Jun 03, 2011 09:31 AM PDT
Products
FileMaker Pro
11.x
FileMaker Pro Advanced
11.x
Operating system requirements

File size: Limited only by disk space, to a maximum of 8 TB (terabytes)
on a hard disk and OS API capability.

Number of files per disk: Limited only by disk space.

Number of files/windows open simultaneously:
Mac OS: Up to 125 files/windows recommended.
Windows: Up to 125 files/windows is recommended. NOTE: the actual number
is determined by factors such as:

- The visibility of the Formatting Bar and the Status Area.
- The machines resources.

It is possible to have more than or less than 125 windows available to
open. If you find that you are unable to open 125 windows, it is
recommended to keep the Formatting Bar, Layout Bar and Status Toolbar
hidden when possible.

Number of remote users per file: Maximum of 9 concurrent clients.

Number of files shared: There is no limit.

Number of sessions via Web browser: Access to web-published database is
limited to 5 concurrent sessions. Note. If another view is opened
through 'New Window' that's still in the same session.

Number of tables per file: 1 million.

Number of records per table: 64 quadrillion total records over life time
of file.

Maximum record size: Limited by disk space or maximum file size.

Number of fields/columns per record: 256 million total fields over life
time of file.

Number of relationships per file: Limited only by disk space or maximum
file size.


and more...