[quote name='CocheseUGA']Not so fast, my friend. That's not true with Halo. MS will never tell us how much they spent to make Halo 3, so it's all a guess. But I'd wager that the budget was easily a medium movie budget if not more.[/QUOTE]
There's no way that Halo 3 cost more than $20 million to make. An average video game costs about $5-$10m depending on production time.
EDIT: I have read there was $10m in advertising costs, so I've added that to the figures.
To give some perspective, Titanic cost $200m to make. That's 10x the cost.
Titanic - $200,000,000 cost, $1,234,000,000 return in 9 months.
Halo 3 - $30,000,000 cost, $170,000,000 return in one day.
The fact is that the film industry's union system and the ridiculous costs of EVERYTHING (catering, film, locations, permits, trailers, generators, CGI, etc) on average I would say make it about 5x more than any given video game.