ManHunt PAL
8B 15 EC 93 41 00 -> 33 d2 90 90 90 90
by ProgScan

Manhunt NTSC
8B 15 2C 8E 41 00 -> 33 d2 90 90 90 90
by ProgScan

Hitman 3 NTSC?
Normal 4/3
C7 85 3C 13 00 00 20 01 00 00 -> C7 85 3C 13 00 00 00 01 00 00
and a bit further you'll find
for Widescreen
C7 85 3C 13 00 00 30 01 00 00 -> C7 85 3C 13 00 00 10 01 00 00
by Progscan

James Bond: Everything or Nothing
Disable 1080i in MS dash

Breakdown NTSC-Jap
83 C9 20 89 0D -> 83 C9 00 89 0D
by akoako (thanks birdtales)

Colin McRae 3 PAL
83 c8 40 a3 40 5f 51 00 -> 83 c8 00 a3 40 5f 51 00
83 c8 20 a3 40 5f 51 00 -> 83 c8 00 a3 40 5f 51 00
By Progscan

Colin McRae 3 NTSC
83 c8 40 a3 c0 5b 51 00 -> 83 c8 00 a3 c0 5b 51 00
83 c8 20 a3 c0 5b 51 00 -> 83 c8 00 a3 c0 5b 51 00
by Shanafan

The Thing
0B CA 89 8D -> D1 E2 89 95
by Progscan

I-Ninja PAL (?)
89 C9 20 01 00 00 89 4A -> 89 C9 00 01 00 00 89 4A
by Terra (thanks Dreamcazman & Bearauto)

I-Ninja NTSC
81 C9 20 01 00 00 89 4A -> 81 C9 00 01 00 00 89 4A
by Joshua Wood confirmed by MikeF

Worms 3D PAL
002486C2 change 3200 -> 3C00
by Dreamcazman

Rolling PAL
At offset 00AC557 change 74 -> EB
by Dreamcazman

Metal Slug 3
C7 44 24 34 20 00 00 00 -> C7 44 24 34 00 00 00 00
by progscan

What are these stupid numbers?
- Read this tutorial first:

But if you'd like, first heres a link to a freeware hex tool.
Lastly heres a list of games that properly support HD resolutions.