Flash multipliers use special wallace tree cells (not lectured) whereas long multiplication using Booth's algorithm is a nice example of a non-fully pipelined multiplier.
Flash multiplier - combinatorial implementation (e.g. a Wallace Tree).
Sequential Long Multiplication
RA=A
RB=B
RC=0
while(RA>0)
{
if odd(RA) RC=RC+RB;
RA = RA >> 1;
RB = RB << 1;
}