Feature request: download manager

Hi!
I'd like to see some advanced functionality in the opera downloader:
- option to set maximum number of simultaneous downloads, queuing the rest
- multi-threadeed download
- use multiple/alternative sources
- option to limit speed (if i want to save some bandwidth for other purposes)
- add multiple urls/links at the same time (drag&drop maybe?)
- option to automatically send dowloaded files to the anti-virus software

And one thing not related to download manager but the page source viewer. There really should be line numbers!
Thanks in advance if you at least think about them