Die Hard Connections
I am now watching Die Hard 2 and realized that there are a few connections between Trespass and some of the Die Hard movies such as:
1, De`voreaux White is in both Die Hard 1 and Trespass
2, Art Evans and William Sadler is in Die Hard 2 and Trespass
3, Robert Zemeckis who wrote Trespass, his ex-wife is in Die Hard 1 (according to John McTiernan`s DVD commentary)
4, James Horner who was supposed to score Trespass had one of his pieces from Aliens tracked in a scene in the end of Die Hard 1
So if you can come up with more connections it would be fun