I'll vouch for the Bladeforums Blue G-10 Native. It was designed for the specific purpose of collecting, but also serves great as an all-around utility or tactical knife. Only 300 of these were made. The Native originally comes with a lightweight fiberglass-reinforced nylon resin handle featuring a web-style pattern. The collectible piece comes with a blue G-10 handle instead, which is of higher quality and greatly reduces slippery conditions. The blade contains the following inscription: "1 of 300", "BladeForums.com", "The Leading Edge of Knife Discussion". There are both plain-edge(my pick) and serrated models (I figure 150 plain and 150 serrated out there?). It comes with a clip that's painted blue, but you can always order a separate non-painted steel clip from Spyderco to replace it and thus avoid wear. I own one of the plain-edge pieces and will soon own a second one.
The piece is beautiful and highly recommended to those who consider the Native to be their favorite Spyderco knife. They are kinda tough to find but you might get as lucky as I did, by finding someone who has them in good condition and is willing to part with his/her piece. I usually got offers between $100 and $125. I don't think I would buy it higher than that last price, unless extras like a Mike Sastre neck sheath and an extra stainless clip were thrown in. I figure they will appreciate in value eventually, given the fact that no other G-10 Natives exist, let alone with a blue colored-handle, blue clip, and writing on blade.
Hope this helps!
-Flood
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-It is pitch black. You are likely to be eaten by a Grue.