Aw smokes, not another emacs vs. vi thread
Just for the record...
I use
Nano!
Congrats on coming over to the dark side, mahesh, I and others here are at your service should you need it.
On that note...
Gnome-Do is, I think, the closest to what FARR does, and
Docky is it's launchbar cousin.
Keep in mind it is written in
Mono, which some find unappealing, but that also means If you're familiar with C#/.NET, then you'll probably find it easier to tweak/extend/bugfix.
KRunner is the KDE counterpart.
Launchy,
Synapse, and
Kupfer are alternatives.
There really isn't an alternative to URL Snooper, aside from the online video download services.
Maybe there's a Firefox extension that does something similar?
AutoHotKey is hard to beat, but there are quite a few powerful scripting languages readily available in most Linux distros, in fact perhaps too many.
(G)Awk+sed,
Perl, and
Lex/Yacc + Flex/Bison are all classics that deserve a look for their powerful regular-expression integration.
Python you already know,
Ruby,
Lua,
Tcl/Tk, are some higher-level ones you might get familiar with, though they all have their quirks and advantages.
PyGTK would be the alternative to PySide, though I'll admit
Qt takes the prize for cross-compatibility.
Glade makes for a good alternative to QtCreator as well.
If you just need to pass a few infos to your shell scripts via simple dialog boxes,
Zenity or it's fork
Yad will do quite nicely.