Note that many websites have their own advertising, unrelated to adware.
From their website:
"Eaccleration reports that Download Receiver and Webcelerator products were discontinued in
2002 when eAcceleration exited the online advertising business."
DownloadReceiver is a component used by eAcceleration (Acceleration Software International Corporation) to download and install their Webcelerator software. It also runs an advertising process called systimer.exe, on startup which connects to eAcceleration's servers at buttonware.net every so often to download a list of pop-up adverts and directions as to when to show them.
There should be a 'Download Receiver' entry in the Control Panel's Add/Remove Programs option. After removing the software you should be able to delete download.exe, eac_drec.dll and systimer.exe from the eAcceleration folder in Program Files\Common Files. You can delete the folder itself if you have nothing else installed from eAcceleration (eg. eAnthology).
Open a DOS command prompt window (from the Start menu, Programs -> Accessories) and enter the commands:
regsvr32 /u "C:\Program Files\Common Files\eAcceleration\eac_drec.dll"
You will need to change the path above if your Program Files folder is elsewhere (eg. on a different drive, or a non-English version of Windows where the name is different).
From the Start menu, choose 'Run' and enter regedit to edit the registry. Find and delete the keys HKEY_LOCAL_MACHINE\Software\Acceleration Software International Corporation, HKEY_CURRENT_USER\Software\Acceleration Software International Corporation and the entry in HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run that points to systimer. You can then restart the computer and delete the files as above.