Making my own oscilliscope?

[MAAASD]

Hello all,
I'm wondering if one can make his own oscilliscope ?
assume i've designed any circuit and i want to check the signal shape at any point of the crct can this be done using my personal computer?
can i design any interface between my circuit and my computer such that i can see the signal on my PC?
maybe?

 

[godfreyl]

... can this be done using my personal computer?

Yes, you can use Visual Analyser software for this.