The iShares Dow Jones Transportation Average ( IYT) ETF was Tuesday's best performer as oil plummeted $2.07 to $50.92, the first move below $51 a barrel since 2005. Meanwhile, holding FedEx ( FDX) jumped 3.5%. The ETF was tacking on $1.55, or 1.8%, to $86.93. The Biotech HOLDRs ( BBH) was also one of the session's winners, rising 0.7% as Genentech ( DNA) and Biogen Idec ( BIIB) were higher by 1.6%. The ETF was gaining 60 cents to $195.90. The Utilities HOLDRs ( UTH) was gaining ground as TXU Corp. ( TXU) was adding 0.7%. The ETF was higher by 60 cents, or 0.5%, to $125.45. Other utility-related ETFs were also faring well. The Utilities Select Sector SPDR ( XLU) ETF was tacking on 0.5% to $36.04. The iShares Dow Jones U.S. Utilities ( IDU) ETF was higher by 0.4% to $88.31. ETFs in crude oil were among the biggest losers. The iPath Goldman Sachs Crude Oil ( OIL) ETF was recently down 3.1% to $31.94. The United States Oil ( USO) ETF was recently falling 3% to $43.29. The SPDR Oil & Gas Equipment & Services ( XES) ETF was off 1.4% to $27.30. The Oil Services HOLDRs ( OIH) was dipping 1.2% to $128.18. The iShares Silver Trust ( SLV) ETF was also one of the losers as silver futures sank 25 cents to $12.62 an ounce. The ETF was shedding $2.39, or 1.9%, to $125.41.