Largely due to the easily obtainable, cross-platform Flash Player, SWF files and FLV Flash video files are very popular on the Web. But buying Flash is a pricey proposition, so to produce these files something a bit cheaper is in order for the average user. In steps Moyea with its Flash Video MX Pro 5 video to Flash converter ($89, free demo). Flash Video MX Pro 5 proved rock-solid in my testing, and it produced high quality output. It sucked up a fair amount of CPU cycles, though; while I could still multi-task, there was a noticeable lag. While it'd be nice to have a CPU utilization throttle, performance was more than acceptable--even with wide-aspect HD resolution source files.
Rudimentary editing in the form of definable start and end points is provided. You may also choose from a number of skins for the playback controls that you can embed in a Flash video file. You may reduce or increase output resolution freely, and there's a handy lock that maintains the video's original aspect ratio--or doesn't--as you desire. Input file types include AVI, MPEG, WMV, MOV, MP4, M4V, 3GP, RM, ASF, RMVB, MKV, DAT, OGM, and ASX; output types include F4V, AVC/H.263/H.264, and Flash 8 to .SWF and .FLV containers.
Flash Video MX Pro is easy on the eye and easy to use. It provides all the options you could ask for, and does a nice job encoding. It's superior in nearly all aspects to the free Riva FLV Encoder 2--especially in output formats (Riva doesn't handle or output wide format or .SWF). However, since the latter is remuneration-less, you might want to try it before dropping $90 on what is admittedly a very nice product.
Note: The demo version adds a watermark to the video and artifacts to the audio that are not present in the output of the paid version.