Restoring database from backup or moving it to another server resets all the creation_date fields (in sys.databases, msdb..backupset etc'). So is there any way to find out the original creation date? Looks like there is one. It is stored in the boot page of the database (page 9) and you'll have to use DBCC PAGE in order to find it.

DBCC TRACEON(3604)
GO
DBCC PAGE (YourDBName, 1, 9, 3)
GO

In the bottom of the page you'll find dbi_crdate field - it is the original creation date.

Boot page fields are poorly documented (I'm being polite - actually, they aren't documented at all). And from the first glance looks like it contains interesting data. For example: dbi_firstSysIndexes, dbi_maxLogSpaceUsed. Here Paul Randal blogged about another column, dbi_dbccLastKnownGood, which is the last time DBCC CHECKDB ran without finding any corruptions in the database.