Please help me understand something here...........  If want to use a
    EEPROM(24C26) memory instead of burning my program into a PIC(16C55)
    directly, do I need an interpreter on the PIC if I compile the
    basicprogram into HEX before upload it to the EEmemory?????

    Or is the interpreter necessary to make the pic work with its
    instructions stored on the memorychip? (I don't think so... I meen
    it's allready in machinelanguage.)

The (smallish) PICs are NOT capable of directly executing instructions from
external memory.  Therefore, the only way to use external memory is to
interpret tokens that are stored there.  Machine language is one possible
type of token, but it doesn't offer very many advantages (since the PIC has
no XCT instruction, nor an ability to execute from (internal) RAM, nor an
ability to do any kind of self-modifying code.  Machine language DOES have
disadvantages - it's 12 bits wide, and not very efficient.  As I've said
before, one of the "successes" of the basic stamp is that the creators
succeeded in defineing a particularly useful small set of primitives.

Additionally, I don't know of ANY processor that can access instructions
from serially accessed program memory - that's sort of the antithesis of
what microprocesor designers use to make things fast.

Now, a downloadable PIC with on-chip instruction RAM (rather like FPGAs)
would be a somewhat interesting beast...

BillW