yes you can download alot of apps, using installous...here is how you do it if you want to know
(if you already jailbroken it and only want to know how to get installous skip ahead)
you should use greenpoison to jailbreak it, it is really simple.
1. turn off your ipod touch
2.open greenpoison
3. plug itouch into the pc
4.start greenpoison and it should tell you to hold switch(2sec), hold switch and home(10 sec) and home button(15sec)<-----i forgot, it would tell you
5. your ipod touch should now be ready and press start jailbreaking or whatever it says...
6.it should automatically finish after 10-15 mins and when it tells you it's done, justdownload cydia from the loader you get in ur ipod touch...thats it
p.s if you've done the first few steps wrong, it cant detect your ipod, you'll have to do it again
Here is the link to greenpoison for ipod touch mc/non mc 4.1
http://www.greenpois0n.com/ (can be used on mac, windows or linux)
to download installous, go into cydia, manage, source, edit and add the following to the window popped out
http://cydia.hackulo.us then add it.
after you've added it, it should appear in your source, so go into it and scroll down, installous should be there, download it and after downloaded, just click in it and search whatever app you want...some app maybe not be there becuz it;s not cracked yet, but there's alot of app in it, hope this helps you!
after jailbroken