LANChile have posted details of a sale from US cities they serve to various parts of Central and South America.

Minimum Stay – 3 days / Return by 15 Dec 13 / Booked in I  class / 14 day Advance Purchase

Miami (Travel by 14 June)

• Quito $699
• Punta Cana $499
• Guayaquil $699
• Bogota $703
• Caracas $899
• Lima $1299
• Santiago $2199
• Buenos Aires $2199

 New York (Travel by 20 June)

• Quito $999
• Lima $2199
• Santiago $3499
• EZE $2999
• Montevideo $2699
• Mendoza $2999

San Francisco (Travel by 13 June)

• Lima $2199
• EZE $2999
• Sao Paulo $2374
• Santiago $2999

Los Angeles

• EZE $2999
• Sao Paulo $2385
• Santiago $3499

 

Checking some dates it look like connections are required in Lima, some to TAM (now merging with LAN), and the return date I checked needed an overnight in Lima.

May not work for everyone, but might be a  way to collect BA Tier Points – although the TAM flight is unlikely to earn any! (This booking would earn 3 *140 Tier Points = 420)