Another space eater in files is the fonts. If embedding fonts when saving the file, the presentation file size will increase by the size of the font file. Need a refresher course on embedding fonts? Review Chapter 4.
This is not always a large contributor to file bloat, since font files are usually less than 100K in size. There are two situations where fonts can contribute to large amounts of file bloat. The first is if Arial Unicode is embedded. The other is there are a lot of embedded fonts in a single file. Both of these situations will cause the file to bloat in a perceptible fashion.