INFO UPDATE 2008-04-19
I just realized some of the wallpapers came with expansion packs. I've updated the info about which ones it is.

This time I've made recolors matching Maxis bricks. Enjoy!

Names from the left: Industrio Brick Wall - Brickfest Wall came with OFB - Justin Uther Brick Wall Treatment - "Backhanded Compliment" Brick Wall Treatment - Coursing Soldier Bricks - Coursing Soldier Bricks in Gray - Industrio Brick Wall Basic Wall Came with UNI

How to use:
First of all, you need the CEP or the chimneys won't be recolourable at all.
Put your fireplace where you want it. If you move it after you recolored it, the chimney will revert to the red bricks. Then, in Buy or Build Mode, select the Design Tool. Click on the chimney, and the recolors will appear. There are quite a few parts to the chimney and they all need to be recolored separately.
If you experience any problems or oddities, please let me know.

Other Sets:
I got a few requests and ended up creating chimney recolors matching all of Maxis outdoor wallpapers (the ones I consider outdoor, that is). There are quite a few recolors, but they're named after their corresponding wallpaper, and you can easily delete the ones you don't want and keep only your favourites. These are the existing sets. If you have any other requests, let me know and I’ll have a look at it.

• Bricks Set - Matching Maxis' brick wallpapers: "Backhanded Compliment" Brick Wall Treatment, Brickfest OFB, Coursing Soldier Bricks, Coursing Soldier Bricks in Gray, Industrio Brick Wall, Industrio Brick Wall Basic UNI & Justin Uther Brick Wall Treatment.

• Timber Siding Set - Matching Maxis' Siding wallpapers Shiver Me Timbers Wood Siding: Army, Bionic Blue, Clay, Grey Slate, Harvest Gold, Ice Blue, Russet & Violet Mist.
• Vinyl Siding Set - Matching Maxis' Siding wallpapers Virtous Vinyl Siding: Coral, Cornflower, Cream, Fog, Ice Blue, Mint, Violet Mist
• Scallop Set - NL Matching the Scallop Wall Shingles wallpapers made by Maxis: Blue, Green, Light Wood, Medium Wood, Orange, Pink, White, Yellow
• Simply Siding Set - Matching Maxis' two simply siding wallpapers, and two others: Duraluminium Siding, Simply Siding in "Hamster", Simply Siding in "Salt", "Wütherbetten" Siding
• Wood Siding Set - Matching Maxis' wood sidings that didn't really fit in any other category: "Naughty Pine" Siding, "Shingle Bells" Wood Shingles, Shingles by Fairytale2You NL, Wood Clapboard OFB, Wood Clapboard Again OFB, Wood Clapboard Reloaded OFB & Wood Clapboard Repeated OFB

• Southwestern Style Stucco Set - UNI Matching Maxis' poured wallpapers "Southwestern Style" Stucco: Banana, Coral, Vanilla, Brick Red, Adventurous White & Calming Blue.
• Stucco Set - Matching Maxis' poured wallpapers Stucco: Cobalt, Craft Work Plastering, Fawn, Honey Pot, Latte, Paste, Putty NL, Rich Rose NL, Sand Dune, Sea Breeze NL, Shadow Grey, Sunshine NL & Way off White

• Masonry Set - Matching Maxis' Masonry Wallpapers: Blunt Opinion Stone Wall UNI, "Brownstone's Revenge" Basic Masonry, Cinders of Joy OFB, Fay's Fieldstone, "Latipsoh" Green Cinderblocks UNI, "Latipsoh" Slate Grey Cinderblocks UNI, "Running the Rapids" Rock Wall UNI , Sandstone Brick OFB, "Say No More" Wall in Grey Stone UNI, "Sedate Stone" Red Stone Wall UNI, "Sedimentary, My Dear" Ashlar Treatment, SlackCo Cinderblocks NL, "Soft Rock" Faux Stone Blocks, "Stack 'Em Up" Stone Wall UNI, "Wall of Thunder" Red Stone Wall UNI

• Majestic Siding Set - Matching The Majestic Siding Collection by Flabaliki: Gracious Green, Bodacious Blue, Sunset Siding, Perspective Purple, Youthful Yellow, Wonderful White & Radical Red

If you like my work, please hit the Thanks-button.

Additional Credits:
Numenor for making the chimneys recolorable
The creators of SimPE