Phiktion wrote:I mean like if I want to record my songs in a huge mix and then how do you import them into it?

Can you be a bit more precise? It seems like you only want a "mixtape" - but you could use any recorder for that. There's no reason you can't use the 404 as a playback provided your set fits in the memory card.
If you import via the flash card - the max 1GB card will only take a mix about 750mB total size (about the same playtime as a CD). Recording to the card via the line-in would let you use most of the card as it doesn't have to carry the original file.
Maybe (more likely?) you want each song on a pad and mix the set live. Obviously same 2 ways to import as above and if you import via the card, the smaller song files can be done in batches so you can delete the originals to free up space for the next batch. It's probably always easier to record from line in - it will save having to shuffle the card between 404 and computer although it will impart more of the 404 "sound" that way which many users seem to like.
You can work crossfades etc but it would take a long time to type the answers and it has all been covered before in threads on the 404 forum here. Tempo matching is a bit trickier - it would help if that's already done in the original song files or you have some short filler/bridge/breakdown samples to use between tracks that won't ever match.
If I had to do it, I think I'd rather have two 404s. One playing, one to get ready and fade between the 2 on a small mixer.
Jim
Just when you think things couldn't get any more exciting - they don't.