Poly counts tend to shoot right up when you model curves, so unfortunately the only way to reduce polys on that desk would be to reduce the curve. That's why you tend to see a lot of right angled desks in games.
Transparent textures are a god send, if used well, they can drastically reduce polycounts. The best example there is the cuffs on the lower image. The chain links are individually modelled, and the cuffs are too - I'm guessing there's about 50 polys per link and about 80 polys per cuff, so that chain and cuff set could cost you about 1300 polys. Now, if you replaced each link with a textured plain, and replace the cuffs with a sorta short tube with the cuff textured around it - you'd cut that down to about 200 polys no problem, and it would'nt look too shabby either - a lot of modellers would just texture the whole thing onto a plain.
You seem to be quite sensible with the bottles etc, it's the little details you add that push the poly count up - avoid things like notches in wood, to cut that little wedge out, it needs to add about 14 polys - PER WEDGE! - again transparent textures can help bring detail into the model in other ways - adding a bent nail to a floorboard for 1 poly, or splinters for broken wood, just a few polys with a transparent texture does the trick without poly bloating.
Van-B
My cats breath smells of cat food.
