Tax Advisor? I need to invest Rs 25000/- in tax saving schemes?

I am a software developer. Kindly suggest me some investment options wherein this amount is exempted from taxable income. Also, after investment the income arising out of the same is also relieved from tax (it is **not mandatory** requirement).

I have already invested in PPF and NSC and have taken LIC policies of long terms. I am looking for making investment wherein the amount is not locked for a longer duration and also at the maturity the tax burden should be minmum. I am not interested in making investment to equity market so please dont suggest me MFs which purely invest in equity market. Mutual fund investing in other than equity market yielding moderate rate of returns (somewhere around 10%-12%) would do.

If you have any other suggestion, kindly share it with me so that it helps me in making decisions.