"Low temperature fusible alloy" -- I've mentioned it for a few years. I've used it to safely remove a specific surface-mount component, say a TQFP from a populated board, while leaving the rest of the board intact. In my case, I simply took some of the filler metal I use to bend thinwall tubing--Cerrobend 158 (158F is the melting temperature of the stuff), powdered some of it (using a file) and tucked the powder around the pins that I wanted to free. No soldering iron necessary--I simply used an ordinary 150 watt PAR spotlight on the area. The alloy melts, dissolves the solder and the part slides right off. Cleanup with a toothbrush. A hot air soldering tool set low would do the same.
Wood's metal slugs are far less expensive than the stuff that Chip-Quik sells. A quick look on eBay shows a 4 ounce stick for $10 shipped. Be aware that technically, these are hazmat, as they contain cadmium and lead--so dispose of safely.