I would assume ROTH IRAs since they already have to pay tax on that income and are most likely already over the income limits for TIRAs. Keough's may work if it qualifes as self-employment income. CPAs are the best people to check with. I just thought I would give it a college try
Your best bet is the Roth IRA. I've checked into this matter with my accontant long time ago. Since the earnings we earned are short-term gains, it is not considered ordinary income. We are not allow to invest in any retirement savings that are tax deductables. The Keogh plan is not appropriate either since we are not considered self-employ. Hope this helps.
Someone who works full time but has a business on the side can put those side earnings into a Keough. Can trading through an entity/prop qualify that as side income that qualifies for Keough? Any CPA/tax guys out there ?