And now for a quick warning:
Per the FAQ, one can earn a hit for transferring hotel points that result in a minimum of 850 dividend miles being deposited. There apparently was an error in the first tier sweep on 9/29 that resulted in transfers of exactly 850 deposited dividend miles *not* counting as a hit. This has since been fixed.

• Best Western: Minimum transfer size for anyone is 5,000 points to 1,000 miles. Elites can apparently buy points, $10 for 1,000 points and they will generally status match most other hotel programs. It should be free and fairly straightforward to transfer points to another Best Western Rewards member for them to do a transfer to their own DM account (see posts #314 to 318). The activity date for the transfer is the date the transfer was initiated. Best Western forum
  
• Choice: Minimum transfer size for anyone (non-elite or elite) is 5,000 Choice points to 1,000 dividend miles. Normal cost to buy points is $11 for 1,000 points. Through December, $11 will get you 1,100 points. It's possible for some to transfer e-rewards to Choice once per quarter for $100=>4,000 points, $60=>2,200 points, or $30=>1,000 points. E-rewards transfer happened instantly for me. Purchasing points might take 24 hours. At least one transfer to a different person's DM account was taken back last year. Transfers to DM take about a week. Choice forum
  
• Club Carlson: Other posts on FT look like minimum transfer size for anyone is 2,000 points to 250 miles, which would mean 8,000 points to 1,000 miles to meet the minimum requirement for a hit. Make sure to do the transfer as one transaction with a quantity of 4 to get the hit. Transfers to a different person's DM account work, or you can just freely transfer to someone else's Club Carlson account. It looks like Club Carlson backdates transfers by one day (which might be good at the end of the promotion if you need one last hit). Club Carlson forum
  
• Hilton: Minimum transfer size for anyone (non-elite or elite) is 10,000 points to 850 miles. Normal cost to buy points is $0.0125 per point for under 10,000 points or $0.01 per point for 10,000 or more points. Note that this means you should never, ever buy 8 or 9 thousand points as it'll be cheaper or the same price to buy 10 thousand points. If you have no stays or partner activity, your account must be open for 90 days before you can purchase points. Purchased points should post within 30 minutes. Also, the ability to transfer AA miles to Hilton points will be going away sometime in the near future. Transfers to DM take about a week. Transfers to another person's DM account should work. Hilton forum
  
• Hyatt: Minimum transfer size for anyone is 5,000 points to 2,000 miles. Normal cost to buy points is $24 per 1,000 points. Through September 30, $24 will get you 1,200 points. Looks like Hyatt transfers post once a month, with the correct activity date. Hyatt forum
  
• La Quinta: Minimum transfer size for anyone is 6,000 points to 1,000 miles. Normal cost to buy points is $11 per 1,000 points. There's a 25% bonus promotion running at the moment (expires Nov 30), which should lower the cost for a hit to $55 if you start with zero LQ points. It's possible to transfer e-rewards once per quarter for $100=>4,000 points, $60=>2,200 points, or $30=>1,000 points. Please note that La Quinta is listed in the Terms and Conditions, but not the Rules, and that US Airways has confirmed via e-mail that LQ counts as a transfer hit. Watch out for activity dates, post 330 says that a transfer initiated 9/24 posted with an activity date of 9/29 so probably not a good end-game hit. Transfers should post on Thursdays.
  
• Marriott: Minimum transfer size for anyone is 10,000 points to 2,000 miles. Normal cost to buy points is $12.50 per 1,000 points. Transfers to another person's DM account should work. Looks like Marriott posts pretty quick. Marriott forum
  
• Priority Club: Minimum transfer size for anyone is 10,000 points to 2,000 miles and must be done by calling in. It's possible to buy 10,000 points for $60 or 5,000 points for $40 and they post pretty much immediately (see post 222). There has been one report of a transfer to a different person's working, even though the previously generally accepted wisdom was that transfers to another DM account won't work, and more recently that the loophole has been closed. Transfers to DM take about a week. Priority Club forum
  
• SPG: Minimum transfer size for anyone (general or preferred members) is 2,500 starpoints, for golds 1,500 starpoints, and for platinums 1 starpoint (although the Grand Slam minimum is 850 starpoints) and you'll receive 1 mile per starpoint. There's a 5,000 point bonus per 20,000 starpoints in a transfer. You can normally buy starpoints for $.035 per point with a 500 point minimum ($17.50/500), but there's a 20% discount through the end of the year which means the cost is $14/500. Transfers to DM take about a week and transfers to a different person's DM account should work. SPG forum
  
• Wyndham: Minimum transfer size for anyone is 8,000 points to 3,200 miles. No way to buy points directly that I can see. Transfers to a different person's DM account should work. Wyndham forum

Accor does not count as a transfer hit.

If you don't want to buy points, it looks like for a lot of programs it's quite easy to earn points with cheap rental cars, see lowfareair's post for more info.