This is a standard cryptic crossword, with a hole in the middle. Solve the clues and you will notice that there is only one O in the entire grid.
Read down the initials of the Across clues and they spell out ROLL THE BALL TO THE HOLE. So, treat the grid as a tilt-maze: the O is the "ball", and let it "roll" orthogonally until it hits a wall, at which point it changes direction. The shortest path from the O to the hole in the middle of the grid is as follows: down, right, up, left, down, right, down, right, up, left. The letters at the points at which the ball changes direction spell out ONE HUNDRED, which is the answer to the puzzle.
Solutions to the clues follow:
Across:
2. TESLA: raTES LAboratory 6. BLEAK: B[lack] + LEAK 10. CENTER: CENT + E.R. 11. EASE: CEASE - C 12. ENNUI: mEaNiNg + WE homophone 14. EATERY: HEATER - H + Y 16. UNHAT: tUrN aHeAd To 18. NICHE: N(I + CH)E 19. LASHED: AS HELD anagram 20. INLAY: IN PLAY - P 21. SUEDE: SUE + D[esigner] + E 23. EVENER: EVE(N[ic]E)R 27. AIDED: A.I. + DEAD - A 29. LAGER: LARGE anagram 31. SANDED: hackS AND EDitors 32. STARE: STA([b]R[ains])E (EATS reversed) 33. LAIN: LA(I)N 34. APEXES: APE + X + E[at]S 35. LYRES: L[ad]Y + RES[t] 36. RANGE: RAN(G)E (EARN anagram)
Down:
1. OCEAN: double definition
2. TENPIN: NIP NET reversed
3. STUN: NUTS reversed
4. LEI: multipLE Idol
5. AREAL: ARE+ [h]AL[f]
6. BEAT: BE(A)T
7. LATHS: HALTS anagram
8. AERIE: A + ERIE
9. KEYED: K + EYE + D
13. NUCLEIN: A CELL UNSEEN LI'L anagram - ALLELES
15. EPHEDRA: HEAD REP anagram
17. HEY: H + EY
21. SAG: GAS reversed
22. DECREE: DE + CREE
23. EDSEL: unmatchED SELler
24. VEALY: belieVE A LYnx
25. NUDIE: NU + DIE
26. RADAR: RA(f) + D + A + R
28. DRESS: DURESS - U
29. LENS: L + ENS ("various cardinal points")
30. ETEN: lEaThErN
32. SPA: deSPAir
The completed grid looks like this:
2006 MIT Mystery Hunt