LONDON --The FTSE 100's (INDEX: ^FTSE) optimism couldn't last, could it? After a couple of weeks when confidence looked to be tentatively returning, the index of the U.K.'s biggest shares is turning tail again and has dropped below the 5,800 level, falling 37 points so far today to 5,770 points.

But things are looking fine for plenty of individual companies in the indexes. Here are three on the up today.

Blinkx (LSE: BLNX.L)
Video technology specialist Blinkx, which is a constituent of our Beginners' Portfolio, jumped 15% to 59.5 pence on the release of a trading update. The firm, whose products are aimed at the targeted-advertising market, told us that first-half revenue of around $80 million is expected, leading to a forecast-beating pre-tax profit of $2.4 million.

Chief executive S. Brian Mukherjee said, "Based on our performance this period and the fundamentals of the sector, we remain confident in our outlook for the rest of the year." Interim results are expected to be announced on Nov. 14.

GB Group (LSE: GBG.L)
GB Group gained 2.5% to 93 pence after releasing a pre-close trading statement ahead of the firm's first-half results. GB, which specializes in identity management and identity security, told us that performance is in line with expectations. We should see a 44% rise in group revenues to 17.7 million and a jump in operating profit of around 55% to 1.4 million pounds.

GB shares have done very well this year, having more than doubled over the past 12 months.

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CSR (LSE: CSR.L)
Shares in CSR gained a modest 1.25% to 342.6 pence on news that the consumer electronics company plans to return up to $285 million to shareholders by means of a tender offer.

The offer, via the agency of JPMorgan, will lead to the purchase of up to 52.7 million shares, with a tender price of between 335 pence and 375 pence. The closing date is Nov. 29.

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