There are a few ways on top of RRSP's to gain tax reduction / deferral; for other readers, some of these options may be preferable to RRSP's themselves for various reasons.
(1) Tax Free Savings Account - Like RRSP's, this is an investment 'vehicle', and you can put just about everything inside it like you can RRSP's. Contributions don't give you an immediate tax deduction, but earnings on those investments will always be 100% tax-free. When you cash in and take money out of the TFSA, no further tax is owing. Particularly for people near retirement, TFSA's are often better than RRSP's, because the full elimination of tax is usually better than a tax deferral of a few years.
(2) Registered Education Savings Plan - while you are near retirement, if you have children yet to complete their education, contribution to an RESP can be advantageous. Contributions do not give an immediate tax deduction, but earnings on the investments are deferred until the money is taken out (and those earnings are partly attributable to your children, who likely will have minimal other income and thus minimal tax if any). As well, you can get a small government grant for each year contributions are made (about $1k per year in value).
(3) Invest in long-term assets that grow in value, rather than provide annual dividends or interest. I assume your RRSP's are relatively diversified, so let's take a look at what asset classes would be best held outside of a tax-efficient vehicle (like RRSP, TFSA, or RESP). If it is an asset that gives you annual income, you pay tax on that immediately every year. If it is an asset that you can control the disposition of (you decide when to sell it), then you can defer recognition of income until you need the money, or until it is otherwise tax-advantaged to do so. Keep in mind that growth-focussed items like this may be in a higher risk class than other investments, so this solution is mostly geared towards those already well diversified and willing to take on additional risk!
This can mean investing in property (where your operating expenses often nearly offset your annual income, meaning you pay minimal tax until you sell, so the true value is often in anticipated property value increases), or non-dividend paying stocks (but be careful that often non-dividend stocks are junior ventures without sufficient cashflow to immediately afford dividends, so risk can be high here), or even investing in precious metals (though the benefit of investing in precious metals is debatable). In general, all these asset classes will also be classified as capital gains when sold, meaning 50% taxable, so there is a benefit to holding them outside of an RRSP [where all income is taxed as 100% regular income when ultimately withdrawn], or TFSA [where all income is tax-free anyway].
Whether any of this makes sense for you will depend more on your risk profile and exact circumstances.
