No question the markets had a strong session today on lighter volume, but it was a good day for the bulls. The session started with a gap-up. They ran sharply in the morning, consolidated late morning into the lunch hour, and then started another rally that took them to new session highs. With about an hour to go they backed off, then tried again to take out the highs again, did so slightly on the S&P 500, but failed to confirm on the NDX, and then rolled over sharply just before the close, although in the last 10 minutes they snapped back again sharply and closed near the highs for the day.

The Dow was up 180 today, the S&P 500 up nearly 20, the Nasdaq 100 nearly 29, and the Philadelphia Semiconductor Index (SOXX) more than 4. The OEX was up 9.60, a 1 1/2 percent gain.

The advance/declines were 24 to 9 positive on the NYSE and 21 to 9 on Nasdaq. But up/down volume was the story today, with about a 5 to 1 positive ratio on New York and a like amount on Nasdaq. The volume, however, was about 1.3 billion on New York and just about 1.7 billion on Nasdaq.

TheTechTrader.com was mostly higher, with some outstanding gainers today. Imclone (IMCL) shot ahead at the opening on drug news, gave back a chunk of it, but still gained almost 7 today on 22 million shares.

Aluminum Corp. of China (ACH) was up 5.40, SunPower (SPWR) up 1.70, Sigma Designs (SIGM) 2.17 on more than 1 million and Chindex (CHDX) 1.39.

Low-priced biotech Corcept Therapeutics (CORT), a portfolio holding of ours, exploded mid-day on some positive drug news, but gave back a big chunk of its gains. We took advantage of that run up to exit at $6. It still closed up with a strong percentage gain, up 1.28 at 4.68 on 3 1/4 million.

Among other gainers, Global Solutions (GSOL) gained 97 cents. Eschelon Corp. (ELON) 79 cents, portfolio position Cepheid (CPHD) up 68 cents, Auxilium Pharmaceuticals (AUXL) another 31 cents today, and DG FastChannel (DGIT) 68 cents.

Shipping stocks were firm but just slightly higher, with DryShips (DRYS) up 45 cents and Excel Maritime (EXM) up 28 cents.

Former Chart of the Week Vicon Industries (VII) gained 55 cents and Research Frontiers (REFR) 41 cents. New portfolio position Harmonic Lightwave (HLIT) gained 53 cents, challenging its 4-month highs.

GigaMedia (GIGM) continued its strong surge of late, up another 40 cents, near its multi-year highs, and new position Cree Inc. (CREE) jumped 62 cents, to close at 27.51.

On the downside, there were no point-plus losers, but JA Solar (JASO) gave back 61 cents , VASCO Data Security (VDSI) 71 cents, FuelTek (FTEK) 57 cents and CTDC 65 cents. Syntax-Brillian (BRLC), a portfolio holding, got hammered at the opening on a delay of their earnings release, but snapped back to close down 51 cents.

Stepping back and reviewing the hourly chart patterns, a last hour sell-off gave back a chunk of the gains, but a very late snapback took back most of that and preserved the gains for the day, with the indices gaining substantially today, closing above key overhead resistance near secondary resistance.

It'll be interesting to see if they can follow through and move further here, but the shorts should be challenged tomorrow morning.

Harry Boxer is a technical consultant to many Wall Street hedge funds and large institutional traders, and author of TheTechTrader.com, a real-time diary of his day, swing and intermediate-term trades. For more of Harry Boxer, sign up for a free 15-day trial to his Real-Time Technical Trading Diary, or sign up for a free 30-day trial to his Top Charts of the Week service.