Possible Adware – S1928.DLL
S1928.dll is a browser toolbar extension that installs with the "StumbleUpon Toolbar". This community-based, word-of-mouth approach to websurfing involves sharing the pages you "stumble upon" with like-minded people who share your interests. This tool is billed as a "completely new way to surf the web. It lets you channel-surf pages which your friends and peers recommend."
S1923.dll adds a link to your browser that can be used to access StubleUpon's "blog this" feature.
If you get a kick out of this utility, then leave the file in place. If not, you can use WinPatrol to remove s1923.dll, stumble.dll, and stumbleupon.dll under your IE Helpers tab. Some find this program to be adware.
Possible Adware
StumbleUpon