For brevity, I'll stick with d20 products.
Crusades of Valour (Mongoose Publishing) The subject matter is right up my alley, but the execution just leaves me cold. How am I supposed to use this?
Ragnarok: Tales Of The Norse Gods (Avalanche Press) The Last Days of Constantinople and even Greenland Saga: The Lost Norse Colony had some ideas I could use, but I'm at a loss for what to do with Ragnarok.
Rappan Athuk: The Dungeon of Graves and Rappan Athuk 2: The Dungeon of Graves: The Middle Levels (Necromancer Games) Rappan Athuk was getting such good buzz in some circles that I picked them up, but they don't do anything for me. Don't get me wrong, I think that brutal high-body count dungeon crawls can be a hoot under the right circumstances, I just don't feel any affection for this example of the genre. Maybe I just don't properly appreciate 'first edition feel.'
Morrow