Off-hand
Pre-raiding: If you are starting to raid, the Fetish of the Primal Gods or the Orb of the Soul Eater is one of the best investments of your badges that you can make. They will last a very long time as a true upgrade doesn't come until Hyjal/BT.
Tier 4 raiding: Karazhan has a couple nice off-hands, but the badge rewards are still your best options.
Tier 5 raiding: The Fathomstone is nice for some crit, but it's not a huge upgrade over the heroic rewards.
Tier 6 raiding: In BT and Hyjal we get some very substantial upgrades. Rage's offhand is significantly better than Shade's though, so be patient and go for that one. Brutallus' offhand is pretty lackluster.
- Chronicle of Dark Secrets (Rage Winterchill - Mount Hyjal) DP: 6044
- Blind-Seers Icon (Shade of Akama - Black Temple) DP: 5088
- Heart of the Pit (Brutallus - Sunwell Plateau) DP: 4992
- Fathomstone (Hydross the Unstable - Serpentshrine Cavern) DP: 3960
- Fetish of the Primal Gods (35 Heroic Badges) DP: 3694
- Jewel of Infinite Possibilities (Netherspite - Karazhan) DP: 3572
- Lamp of Peaceful Radiance (Harbringer Skyriss - The Arcatraz) DP: 3480
- Orb of the Soul Eater (25 Heroic Badges) DP: 3264
- Khadgar's Knapsack (25 Heroic Badges) DP: 3136
- Karrog's Shard (Karrog) DP: 3104
- Talisman of Nightbane (Nightbane - Karazhan) DP: 3016
- Manual of the Nethermancer (Nethermancer Sepethrea - Mechanar) DP: 2712
- Star-Heart Lamp (Temporus - Black Morass) DP: 2608
- Brutal Gladiator's Endgame (Season 4 Arena) DP: 2560
- Karaborian Talisman (Magtheridon - Magtheridon's Lair) DP: 2240
- Vengeful Gladiator's Endgame (Season 3 Arena) DP: 2240